feat(calls): implement advanced multi-model ML noise suppression system

Implement a flexible, multi-model noise suppression pipeline for Element Call/LiveKit integration:

- ML Engines: Added support for RNNoise, Speex, DTLN, and DeepFilterNet 3 models.
- Pipeline Architecture: Implemented modular audio processing in lotus-denoise.js, supporting 'Series Suppression' (running browser-native NSNet2 before ML) and a hardware-style Noise Gate.
- UI & UX Enhancements:
  - Settings UI: Added model comparison chart with CPU/Quality metadata.
  - Tuning: Added Live Microphone Meter for calibrating Noise Gate thresholds.
  - Reporting: Added LotusToast system to alert users when ML suppression fails or falls back to raw input.
- Robustness & Quality:
  - Capture Fidelity: Removed forced 48kHz capture constraints to allow native-rate capture (solving static issues with high-end audio interfaces).
  - Performance: Added WASM SIMD detection with transparent fallback.
  - Capability Detection: Added browser feature detection to disable unsupported ML modes.
- Build Integration: Updated Vite config to self-host all model WASM/tflite assets in /denoise/ directory.

src/app/plugins/call/CallEmbed.ts

@@ -102,6 +102,10 @@ export class CallEmbed {
     intent: ElementCallIntent,
     themeKind: ElementCallThemeKind,
     denoiseMode: NoiseSuppressionMode = 'browser',
+    denoiseModel: string = 'rnnoise',
+    denoiseNativeNS: boolean = true,
+    denoiseGate: boolean = false,
+    denoiseGateThreshold: number = -45,
     initialAudio = true,
     initialVideo = false,
   ): Widget {
@@ -126,8 +130,8 @@ export class CallEmbed {
       lang: 'en-EN',
       theme: themeKind,
       // EC's built-in WebRTC suppressor: on only for 'browser' tier. For 'ml' we
-      // disable it here so RNNoise (the Lotus denoise shim) owns suppression and
-      // the two don't fight each other.
+      // disable it here so EC doesn't do its own extra processing, and let the
+      // Lotus denoise shim (which keeps native NS on) handle the pipeline.
       noiseSuppression: (denoiseMode === 'browser').toString(),
       audio: initialAudio.toString(),
       video: initialVideo.toString(),
@@ -135,9 +139,12 @@ export class CallEmbed {
     });
 
     if (denoiseMode === 'ml') {
-      // Signal the Lotus denoise shim (injected into the EC index.html) to route
-      // the mic through the RNNoise worklet before LiveKit publishes the track.
+      // Signal the Lotus denoise shim to route the mic through the ML processors.
       params.append('lotusDenoise', 'ml');
+      params.append('lotusModel', denoiseModel);
+      params.append('lotusNativeNS', denoiseNativeNS.toString());
+      params.append('lotusGate', denoiseGate.toString());
+      params.append('lotusGateThreshold', denoiseGateThreshold.toString());
     }
 
     if (CallEmbed.startingCall(intent)) {