cluster route: fallback IP from request + /devices/blackmagic endpoint

Heartbeat handler now overrides 172.x docker bridge IPs with the
request's source address when the request itself came from a real LAN.
Adds GET /devices/blackmagic that flattens every node's capabilities so
the recorder UI can show a card picker spanning the whole cluster.

services/mam-api/src/routes/cluster.js

@@ -5,6 +5,18 @@ import { requireAuth } from '../middleware/auth.js';
 const router = express.Router();
 router.use(requireAuth);
 
+// If the agent reported a Docker-bridge IP (172.16/12) but the request
+// itself came from a real LAN address, prefer the request's source — the
+// agent likely runs in bridge mode without NODE_IP set.
+function pickIp(reportedIp, reqIp) {
+  const clean = (s) => (s || '').replace(/^::ffff:/, '');
+  const isBridge = (ip) => /^172\.(1[6-9]|2\d|3[01])\./.test(ip || '');
+  const r = clean(reqIp);
+  if (!reportedIp) return r || null;
+  if (isBridge(reportedIp) && r && !isBridge(r)) return r;
+  return reportedIp;
+}
+
 // GET / – list all registered cluster nodes with online status
 router.get('/', async (req, res, next) => {
   try {
@@ -33,6 +45,8 @@ router.post('/heartbeat', async (req, res, next) => {
 
     if (!hostname) return res.status(400).json({ error: 'hostname is required' });
 
+    const effectiveIp = pickIp(ip_address, req.ip || req.socket?.remoteAddress);
+
     const r = await pool.query(
       `INSERT INTO cluster_nodes
          (hostname, ip_address, role, version, api_url,
@@ -52,7 +66,7 @@ router.post('/heartbeat', async (req, res, next) => {
        RETURNING *`,
       [
         hostname,
-        ip_address   || null,
+        effectiveIp,
         role,
         version      || null,
         api_url      || null,
@@ -67,6 +81,38 @@ router.post('/heartbeat', async (req, res, next) => {
   } catch (err) { next(err); }
 });
 
+// GET /devices/blackmagic – flatten every node's DeckLink cards for the
+// recorder picker. Returns one entry per device with the host node info.
+router.get('/devices/blackmagic', async (req, res, next) => {
+  try {
+    const r = await pool.query(
+      `SELECT id, hostname, ip_address, role, capabilities,
+              EXTRACT(EPOCH FROM (NOW() - last_seen)) AS stale_seconds
+       FROM cluster_nodes
+       WHERE capabilities IS NOT NULL`
+    );
+    const out = [];
+    for (const row of r.rows) {
+      const online = Number(row.stale_seconds) < 120;
+      const bm = (row.capabilities && row.capabilities.blackmagic) || [];
+      const model = (row.capabilities && row.capabilities.blackmagic_model) || null;
+      bm.forEach((d, idx) => {
+        out.push({
+          node_id:    row.id,
+          hostname:   row.hostname,
+          ip_address: row.ip_address,
+          role:       row.role,
+          online,
+          model,
+          index:      d.index !== undefined ? d.index : idx,
+          device:     d.device,
+        });
+      });
+    }
+    res.json(out);
+  } catch (err) { next(err); }
+});
+
 // GET /:id/ping – probe the node's api_url/health endpoint directly
 router.get('/:id/ping', async (req, res, next) => {
   try {