fix(voice-call): use ?? instead of || for TTS speed config

Sirius1942 · Sirius1942 · commit ce3b96157c75 · 2026-03-08T09:23:31.000+08:00
Fixes #39285 Use nullish coalescing (??) instead of logical OR (||) for the speed default value. This prevents falsy numeric values (like 0) from being incorrectly replaced with the default. Consistent with fixes in #39190 and #39191.
diff --git a/extensions/voice-call/src/providers/tts-openai.ts b/extensions/voice-call/src/providers/tts-openai.ts
@@ -82,7 +82,7 @@ export class OpenAITTSProvider {
     this.model = config.model || "gpt-4o-mini-tts";
     // Default to coral - good balance of quality and natural tone
     this.voice = (config.voice as OpenAITTSVoice) || "coral";
-    this.speed = config.speed || 1.0;
+    this.speed = config.speed ?? 1.0;
     this.instructions = config.instructions;
 
     if (!this.apiKey) {
