feat(proxy-engine): add live TTS streaming interactions and incoming number range support

ts/proxybridge.ts

@@ -82,6 +82,19 @@ type TProxyCommands = {
     };
     result: { result: 'digit' | 'timeout' | 'cancelled'; digit?: string };
   };
+  start_tts_interaction: {
+    params: {
+      call_id: string;
+      leg_id: string;
+      text: string;
+      voice?: string;
+      model?: string;
+      voices?: string;
+      expected_digits: string;
+      timeout_ms: number;
+    };
+    result: { result: 'digit' | 'timeout' | 'cancelled'; digit?: string };
+  };
   add_tool_leg: {
     params: {
       call_id: string;
@@ -446,6 +459,40 @@ export async function startInteraction(
   }
 }
 
+/**
+ * Start a live TTS interaction on a specific leg. The first chunk is rendered
+ * up front and the rest streams into the mixer while playback is already live.
+ */
+export async function startTtsInteraction(
+  callId: string,
+  legId: string,
+  text: string,
+  expectedDigits: string,
+  timeoutMs: number,
+  options?: {
+    voice?: string;
+    model?: string;
+    voices?: string;
+  },
+): Promise<{ result: 'digit' | 'timeout' | 'cancelled'; digit?: string } | null> {
+  if (!bridge || !initialized) return null;
+  try {
+    return await sendProxyCommand('start_tts_interaction', {
+      call_id: callId,
+      leg_id: legId,
+      text,
+      expected_digits: expectedDigits,
+      timeout_ms: timeoutMs,
+      voice: options?.voice,
+      model: options?.model,
+      voices: options?.voices,
+    });
+  } catch (error: unknown) {
+    logFn?.(`[proxy-engine] start_tts_interaction error: ${errorMessage(error)}`);
+    return null;
+  }
+}
+
 /**
  * Add a tool leg (recording or transcription) to a call.
  * Tool legs receive per-source unmerged audio from all participants.