Add vue-router, login/setup flow and backend logging

Refactor frontend to route-based navigation with vue-router, add
system setup and login pages with API integration. Add structured
logging, access-log middleware and startup lifecycle to FastAPI
backend.

server/src/app/middleware/logging.py

@@ -0,0 +1,42 @@
+from __future__ import annotations
+
+import logging
+import time
+import uuid
+
+from starlette.middleware.base import BaseHTTPMiddleware, RequestResponseEndpoint
+from starlette.requests import Request
+from starlette.responses import Response
+
+from app.core.logging import get_logger
+
+logger = get_logger("app.middleware.access")
+
+_SKIP_PATHS: frozenset[str] = frozenset({"/", "/docs", "/openapi.json", "/redoc"})
+
+
+class AccessLogMiddleware(BaseHTTPMiddleware):
+    async def dispatch(self, request: Request, call_next: RequestResponseEndpoint) -> Response:
+        if request.url.path in _SKIP_PATHS:
+            return await call_next(request)
+
+        request_id = request.headers.get("X-Request-ID", uuid.uuid4().hex[:12])
+        start = time.perf_counter()
+
+        response = await call_next(request)
+
+        duration_ms = (time.perf_counter() - start) * 1000
+        level = logging.WARNING if response.status_code >= 500 else logging.INFO
+
+        logger.log(
+            level,
+            "%s %s %s %.1fms request_id=%s",
+            request.method,
+            request.url.path,
+            response.status_code,
+            duration_ms,
+            request_id,
+        )
+
+        response.headers["X-Request-ID"] = request_id
+        return response