Fix player UI: sports Highlights pane, scrubber knob, volume knob, description + save-to-playlist

Player/UI fixes:
- Sports (match) Highlights pane: move the toggle click-handler script out of
  the always-false @if(false ...) legacy block so the "Highlights" button opens,
  and emit videoId/isOwner with @json instead of {{ json_encode() }} (escaped
  quotes crashed the data/tab/CRUD block once route keys became hashid strings).
- Progress scrubber knob (video + audio players): center on the track line with
  translate(-50%, -50%); drop the margin-top hack that floated it above the line.
- Music player volume: give the slider wrap height so overflow:hidden no longer
  crops the knob; add a subtle thumb shadow for visibility.
- Music language menu: cap height to available space above the header, sticky
  header, internal scroll; keep controls from auto-hiding while the menu is open.
- Description box: re-check "Show more" overflow at every settle point (fonts,
  images, rAF, tab reopen) so SPA autonext keeps the expand button.

Also bundles pending work: save-to-playlist button component, playlist/channel
views, PlaylistController + NasSyncService, and component-usage tracker updates.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

resources/views/playlists/show.blade.php

@@ -631,7 +631,15 @@ document.addEventListener('DOMContentLoaded', function () {
     document.addEventListener('keydown', e => { if (e.key === 'Escape') closeEditPlaylistModal(); });
 });
 
-function openEditPlaylistModal()  { const m = document.getElementById('editPlaylistModal'); if (m) m.style.display = 'flex'; }
+function openEditPlaylistModal()  {
+    // Reset transient state every time the modal opens so flags from a previous
+    // open (e.g. the user clicked X then closed without saving) don't leak.
+    window._removePlThumb = false;
+    const fi = document.getElementById('playlistThumbnailInput');
+    if (fi) fi.value = '';
+    const m = document.getElementById('editPlaylistModal');
+    if (m) m.style.display = 'flex';
+}
 // Auto-open the edit modal when arriving with #edit (e.g. from playlist-card menu).
 @if($canEdit ?? false)
 if (window.location.hash === '#edit') {
@@ -645,6 +653,9 @@ function handleThumbUpload(input) {
     const file = input.files[0];
     if (!file.type.startsWith('image/')) { showToast('Please select an image file', 'error'); return; }
     if (file.size > 20 * 1024 * 1024) { showToast('Image must be under 20 MB', 'error'); return; }
+    // Picking a new file cancels any pending "remove" intent — otherwise the
+    // controller would receive both `thumbnail` and `remove_thumbnail=1`.
+    window._removePlThumb = false;
     const reader = new FileReader();
     reader.onload = e => {
         document.getElementById('playlistThumbnailPreview').src = e.target.result;