Wire ADS-B end to end: telemetry ingestion + live map overlay

node-26#9. Adds POST /telemetry/adsb (node-key authed via
require_node_service_or_firebase_token) that upserts one Firestore doc per
icao into a new `aircraft` collection, org_id stamped from the reporting
node the same way upload.py defensively stamps `calls`. firestore.rules
gets a matching docInMyOrg()-gated read rule.

Frontend: useAircraft() mirrors useNodes()'s onSnapshot pattern, filtering
docs older than 2 minutes client-side since nothing prunes a stale aircraft
doc server-side yet. MapView gets an opt-in "Aircraft" overlay (unchecked
by default, like the weather radar layer) rendering a rotated plane glyph
per sighting.

Unverified via typecheck — no Node.js/npm on this authoring box yet (see
CLAUDE.md Testing reality). Server side is pytest-covered (test_telemetry.py).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

drb-c2-core/app/models.py

@@ -70,6 +70,21 @@ class NodeRecord(BaseModel):
     override_timeout_at: Optional[datetime] = None
 
 
+class AircraftTrack(BaseModel):
+    """Live ADS-B position, one doc per icao. Overwritten on every sighting —
+    this is a live-map snapshot, not a history (see node-26#9)."""
+    icao: str
+    org_id: Optional[str] = None
+    node_id: str
+    callsign: Optional[str] = None
+    lat: Optional[float] = None
+    lon: Optional[float] = None
+    altitude_ft: Optional[float] = None
+    ground_speed_kt: Optional[float] = None
+    track_deg: Optional[float] = None
+    last_seen: datetime
+
+
 class CommandPayload(BaseModel):
     action: str                      # discord_join / discord_leave / op25_restart
     guild_id: Optional[str] = None