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/lib/components/SpeakerManager.svelte

@@ -34,7 +34,11 @@
 <div class="speaker-manager">
   <h3>Speakers</h3>
   {#if $speakers.length === 0}
-    <p class="empty-hint">No speakers detected yet</p>
+    <p class="empty-hint">No speakers detected</p>
+    <p class="setup-hint">
+      Speaker detection requires a HuggingFace token.
+      Set the <code>HF_TOKEN</code> environment variable and restart.
+    </p>
   {:else}
     <ul class="speaker-list">
       {#each $speakers as speaker (speaker.id)}
@@ -78,6 +82,19 @@
   .empty-hint {
     color: #666;
     font-size: 0.875rem;
+    margin-bottom: 0.25rem;
+  }
+  .setup-hint {
+    color: #555;
+    font-size: 0.75rem;
+    line-height: 1.4;
+  }
+  .setup-hint code {
+    background: rgba(233, 69, 96, 0.15);
+    color: #e94560;
+    padding: 0.1rem 0.3rem;
+    border-radius: 3px;
+    font-size: 0.7rem;
   }
   .speaker-list {
     list-style: none;