fix(proxy): add Codex fallback and preserve provider identity

docs/api/README.md

@@ -644,6 +644,8 @@ console.log(result.content);
 - [ClassifierGenerateFn](type-aliases/ClassifierGenerateFn.md)
 - [ClassifierLogger](type-aliases/ClassifierLogger.md)
 - [ClassifierRouterDeps](type-aliases/ClassifierRouterDeps.md)
+- [AnthropicInvalidRequestFailure](type-aliases/AnthropicInvalidRequestFailure.md)
+- [DeferredClaudeAccountFailure](type-aliases/DeferredClaudeAccountFailure.md)
 - [AllowedCommand](type-aliases/AllowedCommand.md)
 - [OptionSchema](type-aliases/OptionSchema.md)
 - [BaseCommandArgs](type-aliases/BaseCommandArgs.md)
@@ -864,6 +866,11 @@ console.log(result.content);
 - [CodexUsageResponse](type-aliases/CodexUsageResponse.md)
 - [CodexUsageFetchResult](type-aliases/CodexUsageFetchResult.md)
 - [CodexRuntimeAccount](type-aliases/CodexRuntimeAccount.md)
+- [CodexProxyStatusAccountIdentity](type-aliases/CodexProxyStatusAccountIdentity.md)
+- [CodexContentPart](type-aliases/CodexContentPart.md)
+- [CodexResponsesInputItem](type-aliases/CodexResponsesInputItem.md)
+- [CodexResponsesRequest](type-aliases/CodexResponsesRequest.md)
+- [CodexFallbackResult](type-aliases/CodexFallbackResult.md)
 - [Unknown](type-aliases/Unknown.md)
 - [UnknownRecord](type-aliases/UnknownRecord.md)
 - [UnknownArray](type-aliases/UnknownArray.md)

docs/api/type-aliases/AnthropicInvalidRequestFailure.md

@@ -0,0 +1,37 @@
+[**NeuroLink API Reference**](../README.md)
+
+---
+
+[NeuroLink API Reference](../README.md) / AnthropicInvalidRequestFailure
+
+# Type Alias: AnthropicInvalidRequestFailure
+
+> **AnthropicInvalidRequestFailure** = `object`
+
+Defined in: [types/claudeProxy.ts:6](https://github.com/juspay/neurolink/blob/release/src/lib/types/claudeProxy.ts#L6)
+
+A deterministic upstream validation failure that must reach the caller.
+
+## Properties
+
+### status
+
+> **status**: `number`
+
+Defined in: [types/claudeProxy.ts:7](https://github.com/juspay/neurolink/blob/release/src/lib/types/claudeProxy.ts#L7)
+
+---
+
+### body
+
+> **body**: `string`
+
+Defined in: [types/claudeProxy.ts:8](https://github.com/juspay/neurolink/blob/release/src/lib/types/claudeProxy.ts#L8)
+
+---
+
+### contentType?
+
+> `optional` **contentType?**: `string`
+
+Defined in: [types/claudeProxy.ts:9](https://github.com/juspay/neurolink/blob/release/src/lib/types/claudeProxy.ts#L9)

docs/api/type-aliases/CodexAuthFile.md

@@ -8,7 +8,7 @@
 
 > **CodexAuthFile** = `object`
 
-Defined in: [types/codex.ts:26](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L26)
+Defined in: [types/codex.ts:30](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L30)
 
 Shape of `~/.codex/auth.json` written by the Codex CLI.
 
@@ -18,28 +18,28 @@ Shape of `~/.codex/auth.json` written by the Codex CLI.
 
 > `optional` **auth_mode?**: `string`
 
-Defined in: [types/codex.ts:27](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L27)
+Defined in: [types/codex.ts:31](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L31)
 
 ---
 
 ### OPENAI_API_KEY?
 
 > `optional` **OPENAI_API_KEY?**: `string` \| `null`
 
-Defined in: [types/codex.ts:28](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L28)
+Defined in: [types/codex.ts:32](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L32)
 
 ---
 
 ### tokens?
 
 > `optional` **tokens?**: [`CodexAuthFileTokens`](CodexAuthFileTokens.md)
 
-Defined in: [types/codex.ts:29](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L29)
+Defined in: [types/codex.ts:33](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L33)
 
 ---
 
 ### last_refresh?
 
 > `optional` **last_refresh?**: `string`
 
-Defined in: [types/codex.ts:30](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L30)
+Defined in: [types/codex.ts:34](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L34)

docs/api/type-aliases/CodexAuthFileTokens.md

@@ -8,7 +8,7 @@
 
 > **CodexAuthFileTokens** = `object`
 
-Defined in: [types/codex.ts:18](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L18)
+Defined in: [types/codex.ts:22](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L22)
 
 Token block inside `~/.codex/auth.json`.
 
@@ -18,28 +18,28 @@ Token block inside `~/.codex/auth.json`.
 
 > `optional` **id_token?**: `string`
 
-Defined in: [types/codex.ts:19](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L19)
+Defined in: [types/codex.ts:23](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L23)
 
 ---
 
 ### access_token
 
 > **access_token**: `string`
 
-Defined in: [types/codex.ts:20](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L20)
+Defined in: [types/codex.ts:24](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L24)
 
 ---
 
 ### refresh_token?
 
 > `optional` **refresh_token?**: `string`
 
-Defined in: [types/codex.ts:21](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L21)
+Defined in: [types/codex.ts:25](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L25)
 
 ---
 
 ### account_id?
 
 > `optional` **account_id?**: `string`
 
-Defined in: [types/codex.ts:22](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L22)
+Defined in: [types/codex.ts:26](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L26)

docs/api/type-aliases/CodexContentPart.md

@@ -0,0 +1,13 @@
+[**NeuroLink API Reference**](../README.md)
+
+---
+
+[NeuroLink API Reference](../README.md) / CodexContentPart
+
+# Type Alias: CodexContentPart
+
+> **CodexContentPart** = \{ `type`: `"input_text"`; `text`: `string`; \} \| \{ `type`: `"output_text"`; `text`: `string`; \} \| \{ `type`: `"input_image"`; `image_url`: `string`; \}
+
+Defined in: [types/codex.ts:114](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L114)
+
+A text or image content part accepted by the Codex Responses backend.

docs/api/type-aliases/CodexFallbackResult.md

@@ -0,0 +1,45 @@
+[**NeuroLink API Reference**](../README.md)
+
+---
+
+[NeuroLink API Reference](../README.md) / CodexFallbackResult
+
+# Type Alias: CodexFallbackResult
+
+> **CodexFallbackResult** = `object`
+
+Defined in: [types/codex.ts:158](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L158)
+
+Fully buffered Codex result rendered back as an Anthropic response.
+
+## Properties
+
+### text
+
+> **text**: `string`
+
+Defined in: [types/codex.ts:159](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L159)
+
+---
+
+### toolCalls
+
+> **toolCalls**: `NonNullable`\<[`InternalResult`](InternalResult.md)\[`"toolCalls"`\]\>
+
+Defined in: [types/codex.ts:160](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L160)
+
+---
+
+### usage?
+
+> `optional` **usage?**: `NonNullable`\<[`InternalResult`](InternalResult.md)\[`"usage"`\]\>
+
+Defined in: [types/codex.ts:161](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L161)
+
+---
+
+### finishReason
+
+> **finishReason**: `"end_turn"` \| `"tool_use"`
+
+Defined in: [types/codex.ts:162](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L162)

docs/api/type-aliases/CodexImportedCredential.md

@@ -8,7 +8,7 @@
 
 > **CodexImportedCredential** = `object`
 
-Defined in: [types/codex.ts:34](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L34)
+Defined in: [types/codex.ts:38](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L38)
 
 Result of importing a Codex credential (from auth.json or the OAuth flow).
 
@@ -18,31 +18,31 @@ Result of importing a Codex credential (from auth.json or the OAuth flow).
 
 > **accessToken**: `string`
 
-Defined in: [types/codex.ts:35](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L35)
+Defined in: [types/codex.ts:39](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L39)
 
 ---
 
 ### refreshToken?
 
 > `optional` **refreshToken?**: `string`
 
-Defined in: [types/codex.ts:36](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L36)
+Defined in: [types/codex.ts:40](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L40)
 
 ---
 
 ### idToken?
 
 > `optional` **idToken?**: `string`
 
-Defined in: [types/codex.ts:37](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L37)
+Defined in: [types/codex.ts:41](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L41)
 
 ---
 
 ### accountId?
 
 > `optional` **accountId?**: `string`
 
-Defined in: [types/codex.ts:39](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L39)
+Defined in: [types/codex.ts:43](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L43)
 
 ChatGPT account id (from auth.json or decoded from the access token).
 
@@ -52,7 +52,7 @@ ChatGPT account id (from auth.json or decoded from the access token).
 
 > `optional` **expiresAt?**: `number`
 
-Defined in: [types/codex.ts:41](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L41)
+Defined in: [types/codex.ts:45](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L45)
 
 Epoch ms when the access token expires (decoded from the JWT `exp`).
 
@@ -62,7 +62,7 @@ Epoch ms when the access token expires (decoded from the JWT `exp`).
 
 > `optional` **planType?**: `string`
 
-Defined in: [types/codex.ts:43](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L43)
+Defined in: [types/codex.ts:47](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L47)
 
 ChatGPT plan type decoded from the token, for display only.
 
@@ -72,6 +72,6 @@ ChatGPT plan type decoded from the token, for display only.
 
 > `optional` **email?**: `string`
 
-Defined in: [types/codex.ts:45](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L45)
+Defined in: [types/codex.ts:49](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L49)
 
 Account email decoded from the id token, for the account label.

docs/api/type-aliases/CodexProxyStatusAccountIdentity.md

@@ -0,0 +1,13 @@
+[**NeuroLink API Reference**](../README.md)
+
+---
+
+[NeuroLink API Reference](../README.md) / CodexProxyStatusAccountIdentity
+
+# Type Alias: CodexProxyStatusAccountIdentity
+
+> **CodexProxyStatusAccountIdentity** = \{ `provider`: `"anthropic"`; `key`: `string`; \} \| \{ `provider`: `"codex"`; `key`: `string`; \} \| \{ `provider`: `"other"`; `key`: `null`; \}
+
+Defined in: [types/codex.ts:108](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L108)
+
+Provider-qualified account identity used by proxy status rendering.

docs/api/type-aliases/CodexRateLimitWindow.md

@@ -8,7 +8,7 @@
 
 > **CodexRateLimitWindow** = `object`
 
-Defined in: [types/codex.ts:58](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L58)
+Defined in: [types/codex.ts:62](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L62)
 
 One rate-limit window as reported by the Codex backend (primary/secondary).
 
@@ -18,31 +18,31 @@ One rate-limit window as reported by the Codex backend (primary/secondary).
 
 > `optional` **used_percent?**: `number` \| `null`
 
-Defined in: [types/codex.ts:59](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L59)
+Defined in: [types/codex.ts:63](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L63)
 
 ---
 
 ### window_minutes?
 
 > `optional` **window_minutes?**: `number` \| `null`
 
-Defined in: [types/codex.ts:60](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L60)
+Defined in: [types/codex.ts:64](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L64)
 
 ---
 
 ### resets_in_seconds?
 
 > `optional` **resets_in_seconds?**: `number` \| `null`
 
-Defined in: [types/codex.ts:61](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L61)
+Defined in: [types/codex.ts:65](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L65)
 
 ---
 
 ### reset_after?
 
 > `optional` **reset_after?**: `number` \| `null`
 
-Defined in: [types/codex.ts:65](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L65)
+Defined in: [types/codex.ts:69](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L69)
 
 Seconds until reset. Observed alias of `resets_in_seconds` on some
 responses; accepted defensively so a cooldown lands on the real reset
@@ -54,4 +54,4 @@ instead of degrading to the transient ceiling.
 
 > `optional` **resets_at?**: `number` \| `null`
 
-Defined in: [types/codex.ts:66](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L66)
+Defined in: [types/codex.ts:70](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L70)

docs/api/type-aliases/CodexRateLimits.md

@@ -8,7 +8,7 @@
 
 > **CodexRateLimits** = `object`
 
-Defined in: [types/codex.ts:70](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L70)
+Defined in: [types/codex.ts:74](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L74)
 
 Codex rate-limit block: a primary (short) and secondary (long) window.
 
@@ -18,12 +18,12 @@ Codex rate-limit block: a primary (short) and secondary (long) window.
 
 > `optional` **primary?**: [`CodexRateLimitWindow`](CodexRateLimitWindow.md) \| `null`
 
-Defined in: [types/codex.ts:71](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L71)
+Defined in: [types/codex.ts:75](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L75)
 
 ---
 
 ### secondary?
 
 > `optional` **secondary?**: [`CodexRateLimitWindow`](CodexRateLimitWindow.md) \| `null`
 
-Defined in: [types/codex.ts:72](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L72)
+Defined in: [types/codex.ts:76](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L76)

docs/api/type-aliases/CodexResponsesInputItem.md

@@ -0,0 +1,13 @@
+[**NeuroLink API Reference**](../README.md)
+
+---
+
+[NeuroLink API Reference](../README.md) / CodexResponsesInputItem
+
+# Type Alias: CodexResponsesInputItem
+
+> **CodexResponsesInputItem** = \{ `role`: `"user"` \| `"assistant"`; `content`: [`CodexContentPart`](CodexContentPart.md)[]; \} \| \{ `type`: `"function_call"`; `call_id`: `string`; `name`: `string`; `arguments`: `string`; \} \| \{ `type`: `"function_call_output"`; `call_id`: `string`; `output`: `string`; \}
+
+Defined in: [types/codex.ts:120](https://github.com/juspay/neurolink/blob/release/src/lib/types/codex.ts#L120)
+
+A single item in a Codex Responses request.