call: lint/format cleanup for lotus EC wiring

Resolve the eslint/prettier failures from the previous commit (non-blocking
in CI, but real): drop the banned `void` operator on fire-and-forget
transport.send().catch() calls, prefix the now-unused _denoiseNativeNS
param, and run prettier on the touched files.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

src/app/plugins/call/CallEmbed.ts

@@ -138,7 +138,9 @@ export class CallEmbed {
     themeKind: ElementCallThemeKind,
     denoiseMode: NoiseSuppressionMode = 'browser',
     denoiseModel: string = 'rnnoise',
-    denoiseNativeNS: boolean = true,
+    // [lotus] no longer used by the in-source denoise path; kept positionally
+    // for callers. Prefixed with _ to satisfy no-unused-vars.
+    _denoiseNativeNS: boolean = true,
     denoiseGate: boolean = false,
     denoiseGateThreshold: number = -45,
     initialAudio = true,