feat: Rust sensing server with full DensePose-compatible API

Replace Python FastAPI + WebSocket servers with a single 2.1MB Rust binary
(wifi-densepose-sensing-server) that serves all UI endpoints:

- REST: /health/*, /api/v1/info, /api/v1/pose/current, /api/v1/pose/stats,
  /api/v1/pose/zones/summary, /api/v1/stream/status
- WebSocket: /api/v1/stream/pose (pose_data with 17 COCO keypoints),
  /ws/sensing (raw sensing_update stream on port 8765)
- Static: /ui/* with no-cache headers

WiFi-derived pose estimation: derive_pose_from_sensing() generates 17 COCO
keypoints from CSI/WiFi signal data with motion-driven animation.

Data sources: ESP32 CSI via UDP :5005, Windows WiFi via netsh, simulation
fallback. Auto-detection probes each in order.

UI changes:
- Point all endpoints to Rust server on :8080 (was Python :8000)
- Fix WebSocket sensing URL to include /ws/sensing path
- Remove sensingOnlyMode gating — all tabs init normally
- Remove api.service.js sensing-only short-circuit
- Fix clearPingInterval bug in websocket.service.js

Also removes obsolete k8s/ template manifests.

Co-Authored-By: claude-flow <ruv@ruv.net>

ui/services/websocket.service.js

@@ -309,8 +309,11 @@ export class WebSocketService {
       clearTimeout(connection.reconnectTimer);
     }
 
-    // Clear ping interval
-    this.clearPingInterval(connection.url);
+    // Clear heartbeat timer
+    if (connection.heartbeatTimer) {
+      clearInterval(connection.heartbeatTimer);
+      connection.heartbeatTimer = null;
+    }
 
     // Close WebSocket
     if (connection.ws.readyState === WebSocket.OPEN) {