feat(api): production security, cors hardening, latency optimizations, postman artifacts & frontend documentation

ai-patient-onboarding/app/schemas/onboarding.py

@@ -5,7 +5,7 @@ from pydantic import BaseModel, Field
 class PatientContext(BaseModel):
     id: str = Field(..., min_length=1)
     name: Optional[str] = None
-    age: Optional[int] = None
+    age: Optional[int] = Field(None, ge=0, le=120)
     gender: Optional[str] = None
     abha_id: Optional[str] = None
     phone: Optional[str] = None
@@ -46,6 +46,8 @@ class SendMessageResponse(BaseModel):
     stage: str
     message: str
     status: str
+    response_time_ms: Optional[float] = None
+    response_time_sec: Optional[float] = None
 
 
 class AIStateUpdate(BaseModel):