Bug

In extensions/voice-call/src/providers/stt-openai-realtime.ts:65-66, the constructor uses || (logical OR) instead of ?? (nullish coalescing) for default values:

this.silenceDurationMs = config.silenceDurationMs || 800;
this.vadThreshold = config.vadThreshold || 0.5;

This drops valid 0 values:

• vadThreshold: 0 means maximum VAD sensitivity (detect everything as speech) — valid per the schema z.number().min(0).max(1) and the OpenAI Realtime API
• silenceDurationMs: 0 means no silence padding before triggering end-of-speech

When a user configures vadThreshold: 0, they silently get 0.5 instead.

Expected behavior

Use ?? so that 0 is respected and only undefined/null triggers the default:

this.silenceDurationMs = config.silenceDurationMs ?? 800;
this.vadThreshold = config.vadThreshold ?? 0.5;

Impact

Medium — users who set vadThreshold: 0 for maximum sensitivity get medium sensitivity (0.5) without any error or warning.