fix(web): plugin dir resolver in routes, nmcli AP detection, daemon config reload, upload safety, BDF preview (#655)

* fix(web): plugin dir resolver in routes, nmcli AP detection, daemon config reload, upload safety

- Route plugin lookups (installed list, update, recorded version, config
  form, web UI pages) through the plugin manager's resolver so plugins in
  ledmatrix-<id> directories work.
- Captive-portal detection also sees the nmcli fallback AP (cached).
- WiFi monitor daemon re-reads wifi_config.json when its mtime changes.
- Drop the AP check in disconnect_from_network that could never fire.
- LED status file per WiFiManager; config path falls back to this checkout.
- BDF font preview via src.common.bdf_font.
- Asset uploads validate every file before saving; metadata and calendar
  credentials written atomically; no absolute path in the response;
  asset delete answers 400 for a missing body.
- Coerce string booleans in plugin toggle, on-demand start and AP force.
- SSE broadcaster clears its thread handle before exiting.
- start.py log filter handles every exc_info form.
- Cleanups: unused plugins/fonts partial work, duplicate backup catch-alls,
  raw-config error helper, update-route tidy, redundant imports.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(web): request BDF font previews now that the server renders them

The Fonts tab skipped the preview request for .bdf files because the server
used to refuse them; /fonts/preview now draws BDF with the shared loader.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(web): take the update route's plugin directory from a directory listing

CodeQL flagged the path built from the request's plugin_id (the id was
already validated with safe_path_component, which CodeQL doesn't model; the
same flow on main is alerts 738/739). The directory is now the entry of
plugins_dir matched by name, so nothing built from user input reaches the
filesystem; an id with nothing installed goes to the store manager, which
reports it not found as before.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

* fix(web): read the blueprint's plugin_manager defensively in _plugin_directory

_get_plugin_version now goes through _plugin_directory, which read
api_v3.plugin_manager directly; the attribute exists only once the app sets
it, so test_path_traversal_guards::test_a_real_manifest_is_read failed
when run on its own (order-dependent in the full suite).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

scripts/utils/wifi_monitor_daemon.py

@@ -42,6 +42,8 @@ class WiFiMonitorDaemon:
         """
         self.check_interval = check_interval
         self.wifi_manager = WiFiManager()
+        # mtime of wifi_config.json as last loaded; see _reload_config_if_changed.
+        self._config_mtime = self._config_file_mtime()
         self.running = True
         self.last_state = None
         # Counts consecutive checks where nmcli says "connected" but internet is unreachable.
@@ -57,7 +59,32 @@ class WiFiMonitorDaemon:
         """Handle shutdown signals"""
         logger.info(f"Received signal {signum}, shutting down...")
         self.running = False
-    
+
+    def _config_file_mtime(self):
+        try:
+            return self.wifi_manager.config_path.stat().st_mtime_ns
+        except OSError:
+            return None
+
+    def _reload_config_if_changed(self):
+        """Re-read wifi_config.json when it has changed on disk.
+
+        The web UI's auto-enable toggle (POST /api/v3/wifi/ap/auto-enable)
+        only writes the file; this process read it once at startup, so the
+        toggle did nothing until the daemon restarted. One stat per check.
+        """
+        mtime = self._config_file_mtime()
+        if mtime is None or mtime == self._config_mtime:
+            return
+        before = self.wifi_manager.config.get("auto_enable_ap_mode", True)
+        self.wifi_manager._load_config()
+        # _load_config can itself save (it fills in missing keys), so take
+        # the mtime after it, or that save would trigger another reload.
+        self._config_mtime = self._config_file_mtime()
+        after = self.wifi_manager.config.get("auto_enable_ap_mode", True)
+        if after != before:
+            logger.info(f"wifi_config.json changed: auto_enable_ap_mode={after}")
+
     def run(self):
         """Main daemon loop"""
         logger.info("WiFi Monitor Daemon started")
@@ -78,6 +105,8 @@ class WiFiMonitorDaemon:
         
         while self.running:
             try:
+                self._reload_config_if_changed()
+
                 # One combined check that also returns the state it observed —
                 # the previous flow fetched status before AND after the check
                 # on top of the check's own internal fetch, each one several