Add cancel + progress UI, EngineToggle, and Docker deployment

src/index.css

@@ -357,6 +357,38 @@ body {
   flex-wrap: wrap;
 }
 
+/* --- EngineToggle (M5, D-010) --- */
+
+.engine-toggle {
+  display: flex;
+  align-items: center;
+  gap: 1rem;
+  flex-wrap: wrap;
+  font-size: 0.9rem;
+}
+
+.engine-toggle-label {
+  font-weight: 600;
+}
+
+.engine-option {
+  display: inline-flex;
+  align-items: center;
+  gap: 0.35rem;
+  cursor: pointer;
+}
+
+.engine-option:has(input:disabled) {
+  color: var(--muted);
+  cursor: default;
+}
+
+.engine-toggle-hint {
+  flex-basis: 100%;
+  color: var(--muted);
+  font-size: 0.85rem;
+}
+
 /* --- FileDropzone --- */
 
 .dropzone {
@@ -458,6 +490,25 @@ body {
   font-size: 0.95rem;
 }
 
+/* Cancel for the in-flight file run (D-018) — styled like .copy-button, with
+   a warning accent on hover. */
+.cancel-button {
+  margin-left: 0.75rem;
+  border: 1px solid var(--border);
+  background: transparent;
+  color: inherit;
+  border-radius: 8px;
+  padding: 0.3rem 0.9rem;
+  font-size: 0.85rem;
+  cursor: pointer;
+  transition: border-color 0.15s, color 0.15s;
+}
+
+.cancel-button:hover {
+  border-color: #8b3a3a;
+  color: #f2b8b5;
+}
+
 .error {
   margin: 0;
   padding: 0.75rem 1rem;
@@ -561,6 +612,33 @@ body {
   cursor: default;
 }
 
+.transcript-percent {
+  color: var(--muted);
+  font-weight: normal;
+  font-variant-numeric: tabular-nums;
+}
+
+/* Audio progress of the in-flight file pass (transcribe-progress messages). */
+.transcript-progress {
+  display: flex;
+  align-items: center;
+  gap: 0.75rem;
+  margin-top: 0.6rem;
+}
+
+.transcript-progress progress {
+  flex: 1;
+  height: 6px;
+  accent-color: var(--accent);
+}
+
+.transcript-progress-time {
+  color: var(--muted);
+  font-size: 0.85rem;
+  white-space: nowrap;
+  font-variant-numeric: tabular-nums;
+}
+
 .transcript-text {
   margin: 0.75rem 0 0;
   white-space: pre-wrap;