Fix progress overlay, play-from-position, layout cutoff, speaker info

- Replace progress bar with task checklist showing pipeline steps
  (load model, transcribe, load diarization, identify speakers, merge)
- Fix WaveformPlayer: track ready state, disable controls until loaded,
  play from current position instead of resetting to start
- Fix workspace height calc to prevent bottom content cutoff
- Show HF_TOKEN setup hint in SpeakerManager when no speakers detected
- Add console logging for progress events to aid debugging

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/routes/+page.svelte

@@ -102,6 +102,7 @@
       stage: string;
       message: string;
     }>('pipeline-progress', (event) => {
+      console.log('[voice-to-notes] Progress event:', event.payload);
       const { percent, stage, message } = event.payload;
       if (typeof percent === 'number') transcriptionProgress = percent;
       if (typeof stage === 'string') transcriptionStage = stage;
@@ -387,7 +388,8 @@
     display: flex;
     gap: 1rem;
     padding: 1rem;
-    height: calc(100vh - 3.5rem);
+    height: calc(100vh - 3rem);
+    overflow: hidden;
     background: #0a0a23;
   }
   .main-content {