fix: reduce log tail defaults and add Docker client timeout to prevent security page hanging

dashboard/backend/routers/security.py

@@ -7,7 +7,7 @@ from fastapi import APIRouter, Query
 from config import DOCKER_HOST
 
 router = APIRouter()
-client = docker.DockerClient(base_url=DOCKER_HOST)
+client = docker.DockerClient(base_url=DOCKER_HOST, timeout=10)
 
 _tz_cst = timezone(timedelta(hours=8))
 
@@ -132,8 +132,8 @@ def _parse_caddy_logs(lines: str, limit: int) -> list[dict]:
 
 @router.get("/logs")
 def security_logs(
-    tail: int = Query(500, le=5000),
+    tail: int = Query(200, le=2000),
-    limit: int = Query(200, le=1000),
+    limit: int = Query(100, le=500),
 ):
     """Fetch and parse security-relevant logs from Authelia and Caddy."""
     results = []
@@ -164,7 +164,7 @@ def security_logs(
 
 
 @router.get("/stats")
-def security_stats(tail: int = Query(2000, le=10000)):
+def security_stats(tail: int = Query(500, le=2000)):
     """Aggregated security stats: failed logins, top IPs, hourly timeline."""
     auth_entries = []
     caddy_entries = []