feat(mini-player): custom titlebar with action icons; cover/meta/controls layout polish

- Drop the native titlebar on Windows + Linux (decorations: false in
  open_mini_player); macOS keeps the system titlebar with traffic lights.
- Add a slim 26 px custom titlebar with drag region, current track
  title, and the queue / pin / open-main / close action icons.
- Remove the bottom toolbar — those four buttons now live in the
  titlebar where they're easier to reach.
- Refresh the player layout: cover shrinks 112 → 84 px, the right
  column gets title / artist / transport in a single 84 px-tall block,
  progress bar spans the full width below.
- Add a miniPlayer i18n namespace (showQueue, hideQueue, pinOnTop,
  pinOff, openMainWindow, close, emptyQueue) localized for all 8
  supported locales — previously the tooltips were hard-coded English.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/styles/components.css

@@ -9056,30 +9056,87 @@ html.no-compositing .fsr-lyric-line.fsrl-active .fsr-lyric-word.active {
 }
 
 /* ─ Mini Player window ───────────────────────────────────────────────────── */
-.mini-player {
+/* ── Mini player shell ── outermost wrapper that fills the window ── */
+.mini-player-shell {
   width: 100%;
   height: 100vh;
-  display: grid;
-  grid-template-columns: 112px 1fr;
-  grid-template-rows: auto auto;
-  gap: 10px;
-  padding: 12px;
+  display: flex;
+  flex-direction: column;
   background: var(--bg-app);
   color: var(--text-primary);
-  overflow: hidden;
   user-select: none;
+  overflow: hidden;
   box-sizing: border-box;
 }
 
+/* ── Custom in-page titlebar (Linux + Windows; macOS keeps the native one) ── */
+.mini-player__titlebar {
+  flex-shrink: 0;
+  height: 26px;
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 0 4px 0 10px;
+  background: color-mix(in srgb, var(--bg-app) 85%, var(--bg-card) 15%);
+  border-bottom: 1px solid var(--border-subtle);
+}
+.mini-player__titlebar-title {
+  flex: 1;
+  font-size: 11px;
+  font-weight: 500;
+  color: var(--text-muted);
+  white-space: nowrap;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  letter-spacing: 0.02em;
+}
+.mini-player__titlebar-btn {
+  width: 22px;
+  height: 22px;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+  border: none;
+  background: transparent;
+  color: var(--text-muted);
+  border-radius: 4px;
+  cursor: pointer;
+  transition: background 0.12s, color 0.12s;
+}
+.mini-player__titlebar-btn:hover {
+  background: var(--bg-hover);
+  color: var(--text-primary);
+}
+.mini-player__titlebar-btn--active {
+  color: var(--accent);
+}
+.mini-player__titlebar-btn--close:hover {
+  background: var(--danger);
+  color: var(--ctp-base);
+}
+
+.mini-player {
+  flex: 1;
+  display: grid;
+  grid-template-columns: 84px 1fr;
+  grid-template-rows: 84px auto;
+  gap: 8px 10px;
+  padding: 10px 12px;
+  overflow: hidden;
+  box-sizing: border-box;
+  min-height: 0;
+}
+
 .mini-player--queue-open {
-  grid-template-rows: auto auto 1fr;
+  grid-template-rows: 84px auto 1fr;
 }
 
 .mini-player__art {
-  grid-row: 1 / span 2;
+  grid-column: 1;
+  grid-row: 1;
   aspect-ratio: 1;
-  width: 112px;
-  height: 112px;
+  width: 84px;
+  height: 84px;
   background: var(--bg-card);
   border-radius: 8px;
   overflow: hidden;
@@ -9097,10 +9154,13 @@ html.no-compositing .fsr-lyric-line.fsrl-active .fsr-lyric-word.active {
 }
 
 .mini-player__body {
+  grid-column: 2;
+  grid-row: 1;
   padding: 0 2px;
   display: flex;
   flex-direction: column;
-  gap: 6px;
+  justify-content: space-between;
+  gap: 4px;
   min-width: 0;
 }
 
@@ -9130,7 +9190,6 @@ html.no-compositing .fsr-lyric-line.fsrl-active .fsr-lyric-word.active {
   align-items: center;
   justify-content: center;
   gap: 10px;
-  margin-top: 2px;
 }
 .mini-player__btn {
   display: flex;
@@ -9160,6 +9219,8 @@ html.no-compositing .fsr-lyric-line.fsrl-active .fsr-lyric-word.active {
 }
 
 .mini-player__progress {
+  grid-column: 1 / -1;
+  grid-row: 2;
   display: flex;
   align-items: center;
   gap: 6px;
@@ -9183,12 +9244,6 @@ html.no-compositing .fsr-lyric-line.fsrl-active .fsr-lyric-word.active {
   transition: width 0.25s linear;
 }
 
-.mini-player__toolbar {
-  grid-column: 2;
-  display: flex;
-  gap: 4px;
-  justify-content: flex-end;
-}
 
 .mini-queue-wrap {
   grid-column: 1 / -1;