fix: address remaining CodeRabbit feedback on PR #129

- openapi_test.go: assert exact swagger version "2.0" rather than non-empty
- swagger.yaml + swagger.json: remove enforcement from SetBudgetRequest required
  array — handler defaults it to "hard" when omitted, so the spec was stricter
  than the implementation
- swagger.yaml + swagger.json: change period_start format from date-time to date
  to match runtime serialization (YYYY-MM-DD)

https://claude.ai/code/session_01MCDC1ZUBvDiYdi8n2ePzfJ

Author: claude

packages/engine/internal/server/docs/swagger.json

@@ -860,8 +860,7 @@
                 }
             },
             "required": [
-                "monthly_token_limit",
-                "enforcement"
+                "monthly_token_limit"
             ]
         },
         "server.StatusResponse": {
@@ -909,7 +908,7 @@
                 },
                 "period_start": {
                     "type": "string",
-                    "format": "date-time"
+                    "format": "date"
                 },
                 "prompt_tokens": {
                     "type": "integer"

packages/engine/internal/server/docs/swagger.yaml

@@ -137,7 +137,6 @@ definitions:
         type: integer
     required:
       - monthly_token_limit
-      - enforcement
     type: object
   server.StatusResponse:
     properties:
@@ -169,7 +168,7 @@ definitions:
       completion_tokens:
         type: integer
       period_start:
-        format: date-time
+        format: date
         type: string
       prompt_tokens:
         type: integer

packages/engine/internal/server/openapi_test.go

@@ -22,10 +22,10 @@ func TestHandleOpenAPISpec(t *testing.T) {
 	if err := json.Unmarshal(rec.Body.Bytes(), &doc); err != nil {
 		t.Fatalf("response is not valid JSON: %v", err)
 	}
-	// Spec is Swagger 2.0 (generated by swaggo/swag); verify the version key is present.
-	swaggerVer, _ := doc["swagger"].(string)
-	if swaggerVer == "" {
-		t.Errorf("expected swagger version string, got: %v", doc["swagger"])
+	// Spec is Swagger 2.0 (generated by swaggo/swag); verify exact version.
+	swaggerVer, ok := doc["swagger"].(string)
+	if !ok || swaggerVer != "2.0" {
+		t.Errorf("expected swagger version %q, got: %v", "2.0", doc["swagger"])
 	}
 	if doc["info"] == nil {
 		t.Error("response missing 'info' field")