Fix some frontend display/quality/doc issues

app/routers/debug.py

@@ -4,7 +4,7 @@ import os
 import platform
 import struct
 import sys
-from datetime import datetime, timezone
+from datetime import UTC, datetime
 from typing import Any, Literal
 
 from fastapi import APIRouter
@@ -390,7 +390,7 @@ async def debug_support_snapshot() -> DebugSnapshotResponse:
         is_reconnecting=is_reconnecting,
     )
     return DebugSnapshotResponse(
-        captured_at=datetime.now(timezone.utc).isoformat(),
+        captured_at=datetime.now(UTC).isoformat(),
         system=_build_system_info(),
         application=_build_application_info(),
         health=_build_debug_health_summary(health_data, radio_state=radio_state),

app/routers/radio.py

@@ -473,7 +473,7 @@ async def discover_mesh(request: RadioDiscoveryRequest) -> RadioDiscoveryRespons
                     break
                 try:
                     event = await asyncio.wait_for(events.get(), timeout=remaining)
-                except asyncio.TimeoutError:
+                except TimeoutError:
                     break
 
                 merged = _merge_discovery_result(
@@ -536,7 +536,7 @@ async def trace_path(request: RadioTraceRequest) -> RadioTraceResponse:
             timeout_seconds = _trace_timeout_seconds(send_result)
             try:
                 event = await asyncio.wait_for(response_task, timeout=timeout_seconds)
-            except asyncio.TimeoutError as exc:
+            except TimeoutError as exc:
                 raise HTTPException(status_code=504, detail="No trace response heard") from exc
         finally:
             if not response_task.done():

app/routers/server_control.py

@@ -94,7 +94,7 @@ async def fetch_contact_cli_response(
     while _monotonic() < deadline:
         try:
             result = await mc.commands.get_msg(timeout=2.0)
-        except asyncio.TimeoutError:
+        except TimeoutError:
             continue
         except Exception as exc:
             logger.debug("get_msg() exception: %s", exc)
@@ -196,7 +196,7 @@ async def prepare_authenticated_contact_connection(
                 login_future,
                 timeout=response_timeout,
             )
-        except asyncio.TimeoutError:
+        except TimeoutError:
             logger.warning(
                 "No login response from %s %s within %.1fs",
                 contact_label,