chore(deploy): sync backend from GitHub Actions

app.py

@@ -3,6 +3,8 @@ import subprocess
 import io
 import csv
 import asyncio
+import time
+from collections import defaultdict
 from typing import Dict, List, Optional, Tuple, Union, BinaryIO
 # Load environment variables from .env if present
 try:
@@ -13,7 +15,7 @@ except ImportError:
 
 import numpy as np
 from fastapi import Depends, FastAPI, File, Form, HTTPException, UploadFile, Request
-from fastapi.responses import HTMLResponse
+from fastapi.responses import HTMLResponse, PlainTextResponse
 from fastapi.middleware.cors import CORSMiddleware
 from slowapi import Limiter, _rate_limit_exceeded_handler
 from slowapi.util import get_remote_address
@@ -150,7 +152,60 @@ class SecurityHeadersMiddleware(BaseHTTPMiddleware):
 
 app.add_middleware(SecurityHeadersMiddleware)
 
+_request_metrics = defaultdict(int)
+_request_latency_ms = defaultdict(float)
+
+
+class RequestMetricsMiddleware(BaseHTTPMiddleware):
+    async def dispatch(self, request: Request, call_next):
+        started = time.perf_counter()
+        try:
+            response = await call_next(request)
+        except Exception:
+            _request_metrics[(request.method, request.url.path, "500")] += 1
+            raise
+        elapsed_ms = (time.perf_counter() - started) * 1000.0
+        key = (request.method, request.url.path, str(response.status_code))
+        _request_metrics[key] += 1
+        _request_latency_ms[(request.method, request.url.path)] += elapsed_ms
+        response.headers["X-Response-Time-Ms"] = f"{elapsed_ms:.1f}"
+        return response
+
+
+app.add_middleware(RequestMetricsMiddleware)
+
+
+@app.get("/metrics", include_in_schema=False)
+def metrics():
+    lines = [
+        "# HELP animalmind_requests_total Total HTTP requests by method, path and status.",
+        "# TYPE animalmind_requests_total counter",
+    ]
+    for (method, path, status), count in sorted(_request_metrics.items()):
+        lines.append(
+            f'animalmind_requests_total{{method="{method}",path="{path}",status="{status}"}} {count}'
+        )
+    lines.extend([
+        "# HELP animalmind_request_latency_ms_sum Cumulative request latency in milliseconds.",
+        "# TYPE animalmind_request_latency_ms_sum counter",
+    ])
+    for (method, path), total_ms in sorted(_request_latency_ms.items()):
+        lines.append(
+            f'animalmind_request_latency_ms_sum{{method="{method}",path="{path}"}} {total_ms:.3f}'
+        )
+    lines.extend([
+        "# HELP animalmind_sse_clients Current SSE subscribers.",
+        "# TYPE animalmind_sse_clients gauge",
+        f"animalmind_sse_clients {len(_sse_subscribers)}",
+        "# HELP animalmind_warmup_ready Whether the visual model warm-up completed.",
+        "# TYPE animalmind_warmup_ready gauge",
+        f"animalmind_warmup_ready {1 if _vit_model is not None else 0}",
+    ])
+    return PlainTextResponse("\\n".join(lines) + "\\n", media_type="text/plain; version=0.0.4")
+
+
 # --- Globals: DB pool e Redis client ---
+
 db_pool = None
 redis_conn = None
 vision_warmup = {