Add crunch presets, echo options, and streaming word mode

poc/src/audio-service.ts

@@ -6,6 +6,7 @@
  * them in the transcript, and runs speech to text when a provider is set.
  */
 
+import { statSync } from "node:fs";
 import { AudioManager } from "./audio.js";
 import type { CaptureSegment } from "./capture.js";
 import { CapturePipeline } from "./capture.js";
@@ -146,6 +147,19 @@ export class AudioService {
         return { queued: true, id, position: this.queue.length };
     }
 
+    /** Wait for the wrapper's streaming file to appear, then play it while it grows. */
+    private async playWhenReady(file: string): Promise<void> {
+        for (let attempt = 0; attempt < 400; attempt++) {
+            try {
+                if (statSync(file).size > 44) break;
+            } catch {
+                // not created yet
+            }
+            await new Promise(resolve => setTimeout(resolve, 25));
+        }
+        await this.manager.play(file);
+    }
+
     stop(): void {
         this.queue.length = 0;
         this.manager.stopPlayback();
@@ -350,9 +364,27 @@ export class AudioService {
 
         this.playing = true;
         try {
-            const file = await this.tts.synthesize(item.text, item.options);
-            await this.applyDuck(this.shouldDuck());
-            await this.manager.play(file);
+            // Streaming word mode: the wrapper writes the WAV while it synthesizes, so
+            // playback starts on the first word instead of after the whole line.
+            let streaming: Promise<void> | null = null;
+            const options: TtsOptions = { ...item.options };
+            if (item.options.stream === true) {
+                options.onOutputPath = path => {
+                    streaming = (async () => {
+                        await this.applyDuck(this.shouldDuck());
+                        await this.playWhenReady(path);
+                    })();
+                };
+            }
+
+            const file = await this.tts.synthesize(item.text, options);
+            const pending: Promise<void> | null = streaming;
+            if (pending) {
+                await pending;
+            } else {
+                await this.applyDuck(this.shouldDuck());
+                await this.manager.play(file);
+            }
         } catch (error) {
             console.error("[audio] speak failed:", (error as Error).message);
         } finally {