Local dashboard: plain-language status checklist and C2-free listening

- /api/health: ordered checklist (password, C2 approval, MQTT, SDR, source,
  OP25, decoding, audio, Icecast) with what's wrong and what to do; pure
  build_checks() so every state (incl. Toughny's unapproved node) is tested
- /api/listen: pick P25 control channels / one analog freq / a cached C2
  system, validated in MHz, stored as a local override; OP25 restarted with
  the start failure reason surfaced
- /api/config/system no longer writes a raw blob OP25 can't read
- OP25 resumes after reboot on a locally chosen system, not only C2-assigned
- op25-container: analog (NBFM) config generation fixed (AttributeError +
  wrong field names), /op25/log tail, start refuses without a config,
  status detects a dead multi_rx ("crashed") -- node-26#12
- index.html rebuilt on UI_REDESIGN tokens; scanner drops DMR, shows System key

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

drb-edge-node/app/internal/metadata_watcher.py

@@ -235,6 +235,13 @@ class MetadataWatcher:
         self._last_tx_end: Optional[float] = None  # epoch of the srcaddr 1→0 edge
         self._last_ok_poll: float = 0.0
 
+        # Dashboard-only view of what the OP25 console last said. Read by
+        # /api/health; never consulted by segmentation or attribution.
+        self._terminal_epoch: Optional[float] = None
+        self._terminal_channels: List[Dict[str, Any]] = []
+        self._terminal_trunk: List[Dict[str, Any]] = []
+        self._last_heard: Optional[ConsoleEvent] = None
+
         # Rolling console history for close-time attribution.
         self._console: deque[ConsoleEvent] = deque(maxlen=CONSOLE_HISTORY_MAX)
 
@@ -294,6 +301,7 @@ class MetadataWatcher:
 
         self._last_ok_poll = now
         self._record_console(update, now)
+        self._note_terminal(update, now)
 
         activity = self._snapshot()
         if activity is None or not activity.capturing:
@@ -350,6 +358,18 @@ class MetadataWatcher:
         while self._console and self._console[0].epoch < cutoff:
             self._console.popleft()
 
+    def _note_terminal(self, update: Any, now: float) -> None:
+        """Keep the latest console snapshot for the dashboard. No side effects
+        on segment state — trunk_update/channel_update are not sent on every
+        poll, so the last non-empty one is kept."""
+        self._terminal_epoch = now
+        if update.channels:
+            self._terminal_channels = update.channels
+        if getattr(update, "trunk", None):
+            self._terminal_trunk = update.trunk
+        if self._console:
+            self._last_heard = self._console[-1]
+
     def _is_duplicate_grant(self, event: ConsoleEvent) -> bool:
         for index in range(len(self._console) - 1, -1, -1):
             if len(self._console) - index > _GRANT_DEDUPE_DEPTH:
@@ -898,6 +918,19 @@ class MetadataWatcher:
     def is_active(self) -> bool:
         return self._active_call_id is not None
 
+    @property
+    def console_state(self) -> Dict[str, Any]:
+        """Last thing the OP25 console reported, for /api/health only."""
+        heard = self._last_heard
+        return {
+            "last_poll_epoch": self._terminal_epoch,
+            "channels": self._terminal_channels,
+            "trunk": self._terminal_trunk,
+            "last_heard": None if heard is None else {
+                "epoch": heard.epoch, "tgid": heard.tgid, "name": heard.name, "freq": heard.freq,
+            },
+        }
+
     @property
     def unattributed_segments(self) -> int:
         """Orphan-audio segments discarded since start. Surfaced on /api/status."""