Audio songs: one-folder storage, version-aware download/share, GPU-checked renders

Storage structure
- All audio tracks (primary + per-language) now live in one folder per song with
  unique lowercase names ({slug}-{lang}-{id}); no more tracks/ subfolder.
- Generated renders (download video + HLS) moved into the song's local-only cache/
  subfolder, separated from source files (never synced to NAS, safe to wipe).
- tracks:reorganize artisan command (dry-run default) consolidates legacy files,
  updates DB paths, and deletes orphans + empty folders.
- CLAUDE.md documents the canonical layout as a global rule (identical local + NAS).

Version-aware download & share
- Download MP3/Video and Share now act on the version being played; ?track={id}
  is carried through share links and auto-selects audio + title + flag + about +
  OG/meta on open.

GPU + visualizer
- Setting::gpuUsable() runs a cached health probe (nvidia-smi + nvenc smoke test,
  256x144) before sending any encode to the GPU; falls back to CPU otherwise.
- Visualizer "Download Video" bakes in equal-width, cover-coloured, translucent
  frequency bars; loop-filter rebuild makes generation ~25x faster.

Image cropper
- result-callback mode + per-song cover-slide cropper in upload/edit (modal + mobile).

Co-Authored-By: Claude Opus 4.7 (1M context) <[email protected]>

resources/views/components/video-actions.blade.php

@@ -168,7 +168,7 @@
 
     @if ($video->isShareable())
         <button class="action-btn desktop-action"
-            onclick="openShareModal('{{ $video->share_url }}', '{{ addslashes($video->title) }}', '{{ route('videos.recordShare', $video) }}')">
+            onclick="shareCurrent('{{ $video->share_url }}', '{{ addslashes($video->title) }}', '{{ route('videos.recordShare', $video) }}')">
             <i class="bi bi-share"></i><span>Share</span>
         </button>
     @endif
@@ -271,7 +271,7 @@
 
             @if ($video->isShareable())
                 <button class="dropdown-item"
-                    onclick="openShareModal('{{ $video->share_url }}', '{{ addslashes($video->title) }}', '{{ route('videos.recordShare', $video) }}')">
+                    onclick="shareCurrent('{{ $video->share_url }}', '{{ addslashes($video->title) }}', '{{ route('videos.recordShare', $video) }}')">
                     <i class="bi bi-share"></i> Share
                 </button>
             @endif
@@ -514,6 +514,14 @@ if (!window._slideshowDlInit) {
         document.getElementById('sl-dl-cancel').textContent = 'Close';
     }
 
+    // Share the version the viewer is on: append ?track={id} so the recipient's player
+    // opens directly on that language (window._ytpTrackId; 0 = primary → plain link).
+    window.shareCurrent = function (baseUrl, title, recordUrl) {
+        var t = window._ytpTrackId || 0;
+        var url = t ? baseUrl + (baseUrl.indexOf('?') === -1 ? '?' : '&') + 'track=' + t : baseUrl;
+        if (typeof window.openShareModal === 'function') window.openShareModal(url, title, recordUrl);
+    };
+
     window.startSlideshowDownload = function (routeKey) {
         if (_currentKey && _currentKey !== routeKey) {
             // Different video — reset
@@ -521,6 +529,17 @@ if (!window._slideshowDlInit) {
             _pollTimer = null;
         }
         _currentKey = routeKey;
+
+        // Act on the version the viewer is currently playing: the visualizer toggle AND
+        // the selected language track (window._ytpTrackId; 0 = primary).
+        var vizOn   = localStorage.getItem('audioBarsOn') === '1';
+        var trackId = window._ytpTrackId || 0;
+        var _p = [];
+        if (vizOn)   _p.push('visualizer=1');
+        if (trackId) _p.push('track=' + trackId);
+        var qs    = _p.length ? '?' + _p.join('&') : '';   // generate + download
+        var qsAmp = _p.length ? '&' + _p.join('&') : '';   // appended to progress ?duration=
+
         _maxPct = 0;
         document.getElementById('sl-dl-bar').style.background = '';  // restore gradient
         document.getElementById('sl-dl-cancel').textContent = 'Cancel';
@@ -532,7 +551,7 @@ if (!window._slideshowDlInit) {
         var csrfMeta = document.querySelector('meta[name="csrf-token"]');
         var token = (typeof csrf !== 'undefined' ? csrf : '') || (csrfMeta ? csrfMeta.getAttribute('content') : '');
 
-        fetch('/videos/' + routeKey + '/slideshow/generate', {
+        fetch('/videos/' + routeKey + '/slideshow/generate' + qs, {
             method: 'POST',
             headers: { 'X-CSRF-TOKEN': token, 'Accept': 'application/json' }
         })
@@ -546,7 +565,7 @@ if (!window._slideshowDlInit) {
                 document.getElementById('sl-dl-cancel').style.display = 'none';
                 setTimeout(function () {
                     window._slideshowDlCancel();
-                    window.location.href = '/videos/' + routeKey + '/download';
+                    window.location.href = '/videos/' + routeKey + '/download' + qs;
                 }, 600);
                 return;
             }
@@ -559,7 +578,7 @@ if (!window._slideshowDlInit) {
             _setProgress(2, 'Generating video...');
 
             _pollTimer = setInterval(function () {
-                fetch('/videos/' + routeKey + '/slideshow/progress?duration=' + duration, {
+                fetch('/videos/' + routeKey + '/slideshow/progress?duration=' + duration + qsAmp, {
                     headers: { 'Accept': 'application/json' }
                 })
                 .then(function (r) { return r.json(); })
@@ -581,7 +600,7 @@ if (!window._slideshowDlInit) {
                         document.getElementById('sl-dl-cancel').style.display = 'none';
                         setTimeout(function () {
                             window._slideshowDlCancel();
-                            window.location.href = '/videos/' + routeKey + '/download';
+                            window.location.href = '/videos/' + routeKey + '/download' + qs;
                         }, 600);
                         return;
                     }