feat(V2): /health/ready con ping client + middleware request log strutturato + request_id correlation

- /health/ready: ping di tutti i client (exchange, env) cached con
  timeout 2s, status ready|degraded|not_ready, opt-in 503 via
  READY_FAILS_ON_DEGRADED.
- Middleware mcp.request: 1 riga JSON per HTTP request con request_id,
  method, path, status_code, duration_ms, actor, bot_tag, exchange,
  tool, client_ip, user_agent.
- request_id propagato in request.state, audit log e error envelope per
  correlazione cross-cutting.
- Aggiunto async health() come probe minimo a bybit/alpaca/macro/
  sentiment/deribit (hyperliquid lo aveva già).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/cerbero_mcp/common/audit.py

@@ -74,6 +74,7 @@ def audit_write_op(
     payload: dict[str, Any] | None = None,
     result: dict[str, Any] | None = None,
     error: str | None = None,
+    request_id: str | None = None,
 ) -> None:
     """Emit a structured audit log record per write operation.
 
@@ -86,6 +87,8 @@ def audit_write_op(
     payload: input non-sensibile (qty, side, leverage, ecc.).
     result: output del client (order_id, status, ecc.).
     error: stringa errore se l'operazione ha fallito.
+    request_id: id propagato dal middleware request log per correlazione
+        tra audit log e request log.
     """
     _configure_audit_sink()
     record: dict[str, Any] = {
@@ -97,6 +100,8 @@ def audit_write_op(
         "target": target,
         "payload": payload or {},
     }
+    if request_id is not None:
+        record["request_id"] = request_id
     if result is not None:
         record["result"] = _summarize_result(result)
     if error is not None:

src/cerbero_mcp/common/audit_helpers.py

@@ -58,6 +58,7 @@ async def audit_call(
     """Esegue tool_fn e logga audit (success o error). Riraisola eccezioni."""
     actor = getattr(request.state, "environment", None)
     bot_tag = getattr(request.state, "bot_tag", None)
+    request_id = getattr(request.state, "request_id", None)
     target = _extract_target(params, target_field)
     payload = _safe_dump(params)
 
@@ -72,6 +73,7 @@ async def audit_call(
             target=target,
             payload=payload,
             error=f"{type(e).__name__}: {e}",
+            request_id=request_id,
         )
         raise
 
@@ -93,5 +95,6 @@ async def audit_call(
         target=target,
         payload=payload,
         result=audit_result,
+        request_id=request_id,
     )
     return result

src/cerbero_mcp/common/request_log.py

@@ -0,0 +1,104 @@
+"""Middleware: structured JSON request log per ogni HTTP request.
+
+Emette una riga JSON sul logger ``mcp.request`` con campi correlabili
+all'audit log via ``request_id``. Espone anche ``request_id`` su
+``request.state`` così che handler/exception handler downstream possano
+includerlo nei propri payload.
+"""
+from __future__ import annotations
+
+import logging
+import time
+import uuid
+from collections.abc import Awaitable, Callable
+from datetime import UTC, datetime
+from typing import Any
+
+from fastapi import FastAPI, Request
+from starlette.responses import Response
+
+from cerbero_mcp.common.logging import get_json_logger
+
+_logger = get_json_logger("mcp.request", level=logging.INFO)
+
+
+def _extract_exchange(path: str) -> str | None:
+    """Estrae il nome dell'exchange dal path se è un ``/mcp-{exchange}/...``."""
+    if not path.startswith("/mcp-"):
+        return None
+    rest = path[len("/mcp-"):]
+    end = rest.find("/")
+    if end < 0:
+        return rest or None
+    return rest[:end] or None
+
+
+def _extract_tool(path: str) -> str | None:
+    """Estrae nome tool dal path ``/mcp-X/tools/Y``."""
+    parts = path.split("/")
+    # ["", "mcp-deribit", "tools", "place_order"]
+    if len(parts) >= 4 and parts[2] == "tools":
+        return parts[3] or None
+    return None
+
+
+def install_request_log_middleware(app: FastAPI) -> None:
+    """Aggiunge un middleware HTTP che logga JSON per ogni request."""
+
+    @app.middleware("http")
+    async def request_log(
+        request: Request,
+        call_next: Callable[[Request], Awaitable[Response]],
+    ) -> Response:
+        request_id = uuid.uuid4().hex
+        # Espone request_id per uso downstream (audit, error envelope)
+        request.state.request_id = request_id
+        t0 = time.perf_counter()
+        status_code = 500
+        error: str | None = None
+        response: Response | None = None
+        try:
+            response = await call_next(request)
+            status_code = response.status_code
+        except Exception as e:
+            error = f"{type(e).__name__}: {str(e)[:200]}"
+            raise
+        finally:
+            dur_ms = (time.perf_counter() - t0) * 1000
+            path = request.url.path
+            payload: dict[str, Any] = {
+                "event": "request",
+                "request_id": request_id,
+                "method": request.method,
+                "path": path,
+                "status_code": status_code,
+                "duration_ms": round(dur_ms, 2),
+                "timestamp": datetime.now(UTC).isoformat(),
+            }
+            ua = request.headers.get("user-agent")
+            if ua:
+                payload["user_agent"] = ua[:200]
+            client = request.client
+            if client is not None:
+                payload["client_ip"] = client.host
+            actor = getattr(request.state, "environment", None)
+            if actor:
+                payload["actor"] = actor
+            bot_tag = getattr(request.state, "bot_tag", None)
+            if bot_tag:
+                payload["bot_tag"] = bot_tag
+            exchange = _extract_exchange(path)
+            if exchange:
+                payload["exchange"] = exchange
+            tool = _extract_tool(path)
+            if tool:
+                payload["tool"] = tool
+            if error:
+                payload["error"] = error
+                _logger.error("request", extra=payload)
+            else:
+                _logger.info("request", extra=payload)
+        # response è settato se non c'è stata eccezione (altrimenti
+        # l'eccezione è stata già rilanciata dal blocco except).
+        assert response is not None
+        return response