feat: Feeder-level gateway awareness from /api/packets_seen

Samples recent packets and calls /api/packets_seen to discover which
physical MQTT gateways hear each node. Per-gateway RSSI and SNR.

UnifiedNode:
- feeder_gateways list with gateway_id, gateway_name, avg_rssi, avg_snr
- feeder_count, feeder_best (strongest signal), feeder_worst

MeshviewSource:
- Added feeders to ENDPOINT_SCHEDULE (every 20 ticks / 10 min)
- _fetch_feeders() samples 20 packets and queries packets_seen
- Auto-disables if endpoint returns 404

MeshDataStore:
- _enrich_feeder_data() aggregates gateway data across all sources
- _normalize_node_id() helper for hex/decimal conversion
- get_feeder_map() shows per-gateway coverage statistics
- get_node_feeders() returns sorted gateway list for a node

MeshReporter:
- Node detail shows feeder gateways with signal strength
- Tier 1 shows total unique gateways and avg per node

Discovered gateways: AIDA, BKBS, STLR, N7MH, stor, JTS

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

meshai/mesh_reporter.py

@@ -457,6 +457,19 @@ class MeshReporter:
             if pb["critical"]: parts.append(f"{pb['critical']} battery critical")
             lines.append(f"POWER (infra): {', '.join(parts)}")
 
+        # Feeder gateway summary
+        all_nodes = list(health.nodes.values())
+        nodes_with_feeders = [n for n in all_nodes if getattr(n, 'feeder_count', 0) > 0]
+        if nodes_with_feeders:
+            total_unique_gw = set()
+            for n in nodes_with_feeders:
+                for gw in n.feeder_gateways:
+                    total_unique_gw.add(gw["gateway_id"])
+
+            avg_feeders = sum(n.feeder_count for n in nodes_with_feeders) / len(nodes_with_feeders)
+            lines.append("")
+            lines.append(f"FEEDERS: {len(total_unique_gw)} physical gateways, avg {avg_feeders:.1f} per node ({len(nodes_with_feeders)} nodes sampled)")
+
         # Source health section
         lines.extend(self._build_source_health_section())
 
@@ -935,6 +948,27 @@ class MeshReporter:
             if node.sources:
                 lines.append(f"  Seen by: {', '.join(node.sources)} ({len(node.sources)} sources)")
 
+            # Feeder gateways
+            if node.feeder_gateways:
+                lines.append(f"  Feeders ({node.feeder_count} gateways):")
+                # Sort by signal strength (best RSSI first, closest to 0)
+                sorted_gw = sorted(
+                    node.feeder_gateways,
+                    key=lambda g: g.get("avg_rssi") or -999,
+                    reverse=True
+                )
+                for gw in sorted_gw[:8]:  # Top 8
+                    name_str = gw.get("gateway_name") or gw["gateway_id"]
+                    parts = []
+                    if gw.get("avg_rssi") is not None:
+                        parts.append(f"RSSI {gw['avg_rssi']:.0f}")
+                    if gw.get("avg_snr") is not None:
+                        parts.append(f"SNR {gw['avg_snr']:.1f}")
+                    sig_str = f" [{', '.join(parts)}]" if parts else ""
+                    lines.append(f"    {name_str}{sig_str}")
+                if len(sorted_gw) > 8:
+                    lines.append(f"    ...and {len(sorted_gw) - 8} more")
+
         # Neighbors section
         if node.neighbors:
             lines.append("")