fix: WCAG AAA contrast compliance, speed menu z-index, custom app icon

- Fix all text colors to meet WCAG 2.2 AAA 7:1 contrast ratios against
  dark backgrounds (--textMuted, --textDim, hover states across playlist,
  player, panels, tooltips)
- Fix speed menu rendering behind seek bar by correcting z-index stacking
  context (.controls z-index:10, .miniCtl z-index:3, .seek z-index:2)
- Replace default Tauri icons with custom TutorialVault icon across all
  required sizes (32-512px PNGs, ICO, ICNS, Windows Square logos)
- Update README: Fraunces → Bricolage Grotesque font reference
- Add collapsible dock pane persistence and keyboard-adjustable dividers

src/player.ts

@@ -155,6 +155,12 @@ export function initPlayer(): void {
       if (d > 0) seek.value = String(Math.round((t / d) * 1000));
       updateSeekFill();
       updateTimeReadout();
+      // Update active row's mini progress bar in real time
+      const activeRow = document.querySelector('.row.active');
+      if (activeRow && d > 0) {
+        const bar = activeRow.querySelector('.rowProgress') as HTMLElement;
+        if (bar) bar.style.width = clamp((t / d) * 100, 0, 100) + '%';
+      }
     }
     cb.updateInfoPanel?.();
   });
@@ -434,8 +440,8 @@ export function cycleSpeed(delta: number): void {
   cb.updateInfoPanel?.();
   cb.notify?.(`Speed: ${r}x`);
   setSuppressTick(true);
-  if (library) { api.setFolderRate(r).catch(() => {}); }
-  setSuppressTick(false);
+  if (library) { api.setFolderRate(r).catch(() => {}).finally(() => setSuppressTick(false)); }
+  else { setSuppressTick(false); }
 }
 
 /** Load a video by index and handle the onloadedmetadata callback. */
@@ -530,7 +536,7 @@ export function buildSpeedMenu(active: number): void {
     left.appendChild(dot); left.appendChild(txt);
     row.appendChild(left);
 
-    row.onclick = async () => {
+    row.onclick = () => {
       closeSpeedMenu();
       const r = clamp(Number(s), 0.25, 3);
       player.playbackRate = r;
@@ -540,8 +546,8 @@ export function buildSpeedMenu(active: number): void {
       buildSpeedMenu(r);
       cb.updateInfoPanel?.();
       setSuppressTick(true);
-      if (library) { try { await api.setFolderRate(r); } catch (_) {} }
-      setSuppressTick(false);
+      if (library) { api.setFolderRate(r).catch(() => {}).finally(() => setSuppressTick(false)); }
+      else { setSuppressTick(false); }
     };
     speedMenu.appendChild(row);
   }