fix(providers): lift @ts-nocheck on Gemini + OpenRouter

GeminiProvider needed one type addition: GeminiGenerationConfig
gains a responseSchema?: Record<string, unknown> field so the
constrained-decoding path at line 741 type-checks.

OpenRouterProvider needed one signature fix: line 487 was passing
apiResponse.id (string) to OpenRouterProviderError's httpStatus
(number) slot. Moved it to details as { responseId: apiResponse.id }.

OpenAIProvider keeps @ts-nocheck because the file references a
phantom OpenAIAPITypes namespace that was never imported — that
needs the openai SDK as a real dependency, not a one-liner.

Author: jddunn

src/core/llm/providers/implementations/GeminiProvider.ts

@@ -1,4 +1,3 @@
-// @ts-nocheck
 // File: backend/agentos/core/llm/providers/implementations/GeminiProvider.ts
 
 /**
@@ -116,6 +115,7 @@ interface GeminiGenerationConfig {
   topK?: number;
   stopSequences?: string[];
   responseMimeType?: string;
+  responseSchema?: Record<string, unknown>;
 }
 
 /** A single function declaration for tool calling. */

src/core/llm/providers/implementations/OpenRouterProvider.ts

@@ -1,5 +1,4 @@
 // File: backend/agentos/core/llm/providers/implementations/OpenRouterProvider.ts
-// @ts-nocheck
 /**
  * @fileoverview Implements the IProvider interface for OpenRouter, a service that
  * provides access to a wide variety of LLMs from different providers through a unified API.
@@ -485,7 +484,7 @@ export class OpenRouterProvider implements IProvider {
   ): ModelCompletionResponse {
     const choice = apiResponse.choices[0];
     if (!choice) {
-      throw new OpenRouterProviderError("Received empty choices array from OpenRouter.", "API_RESPONSE_MALFORMED", apiResponse.id);
+      throw new OpenRouterProviderError("Received empty choices array from OpenRouter.", "API_RESPONSE_MALFORMED", undefined, undefined, { responseId: apiResponse.id });
     }
 
     const usage: ModelUsage | undefined = apiResponse.usage ? {