Wire ADS-B end to end: secondary-sdr container running dump1090

node-26#9. New secondary-sdr-container claims the node's SECOND physical
SDR (RTL-SDR index 1 — op25 always claims index 0; no serial-based binding
yet, same gap op25 itself has). Its control API (start/stop/status/data,
mirroring op25_controller.py) launches dump1090 in adsb mode and exposes
the decoded aircraft.json snapshot; AIS mode 400s until it's wired next.

edge-node: on_config_push starts/stops it when secondary_sdr_mode changes,
lifespan resumes it after a restart if already configured, and a new
telemetry_uplink_loop polls its /secondary/data every 10s and POSTs
non-empty snapshots to C2's new /telemetry/adsb (same bearer-key pattern
call_recorder.py already uses for audio upload).

UNVERIFIED: this container has not been built or run against real hardware
in this session (sandboxed authoring machine, no docker) — dump1090's
--write-json field names are believed correct from its docs but not
confirmed against a real capture. Build + hardware smoke test before this
reaches a real node.

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

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

@@ -0,0 +1,41 @@
+import asyncio
+
+import httpx
+
+from app.config import settings
+from app.internal import credentials
+from app.internal.config_manager import load_node_config
+from app.internal.logger import logger
+from app.internal.secondary_sdr_client import secondary_sdr_client
+
+# How often the second-SDR decoder's current snapshot is forwarded to C2
+# (node-26#9). This is a live-map overlay, not a flight/vessel history, so
+# there is no backlog/retry on a missed tick — the next one supersedes it.
+UPLINK_INTERVAL_SECONDS = 10
+
+
+async def _post_snapshot(path: str, body: dict) -> None:
+    if not settings.c2_url:
+        return
+    api_key = credentials.get_api_key()
+    if not api_key:
+        return
+    headers = {"Authorization": f"Bearer {api_key}"}
+    try:
+        async with httpx.AsyncClient(timeout=10) as client:
+            r = await client.post(f"{settings.c2_url}{path}", json=body, headers=headers)
+            r.raise_for_status()
+    except Exception as e:
+        logger.debug(f"Telemetry uplink to {path} failed: {e}")
+
+
+async def telemetry_uplink_loop():
+    while True:
+        await asyncio.sleep(UPLINK_INTERVAL_SECONDS)
+        config = load_node_config()
+        if config.secondary_sdr_mode != "adsb":
+            continue
+        snapshot = await secondary_sdr_client.data()
+        if not snapshot or not snapshot.get("aircraft"):
+            continue
+        await _post_snapshot("/telemetry/adsb", {"aircraft": snapshot["aircraft"]})