refactor(backend): extract api_keys routes

Author: DevanshuNEU

backend/routes/api_keys.py

@@ -0,0 +1,59 @@
+"""API key management and metrics routes."""
+from fastapi import APIRouter, Depends
+from pydantic import BaseModel
+
+from dependencies import api_key_manager, rate_limiter, metrics
+from middleware.auth import require_auth, AuthContext
+
+router = APIRouter(prefix="/api", tags=["API Keys"])
+
+
+class CreateAPIKeyRequest(BaseModel):
+    name: str
+    tier: str = "free"
+
+
+@router.get("/metrics")
+async def get_performance_metrics(
+    auth: AuthContext = Depends(require_auth)
+):
+    """Get performance metrics and monitoring data."""
+    return metrics.get_metrics()
+
+
+@router.post("/keys/generate")
+async def generate_api_key(
+    request: CreateAPIKeyRequest,
+    auth: AuthContext = Depends(require_auth)
+):
+    """Generate a new API key."""
+    new_key = api_key_manager.generate_key(
+        name=request.name,
+        tier=request.tier,
+        user_id=auth.user_id
+    )
+    
+    return {
+        "api_key": new_key,
+        "tier": request.tier,
+        "name": request.name,
+        "message": "Save this key securely - it won't be shown again"
+    }
+
+
+@router.get("/keys/usage")
+async def get_api_usage(
+    auth: AuthContext = Depends(require_auth)
+):
+    """Get current API usage stats."""
+    usage = rate_limiter.get_usage(auth.identifier)
+    
+    return {
+        "tier": auth.tier,
+        "limits": {
+            "free": {"minute": 20, "hour": 200, "day": 1000},
+            "pro": {"minute": 100, "hour": 2000, "day": 20000},
+            "enterprise": {"minute": 500, "hour": 10000, "day": 100000}
+        }[auth.tier],
+        "usage": usage
+    }