Add multi-language audio tracks and self-hosted flag-icons

Introduce per-video language support and multiple audio tracks
(VideoAudioTrack model + migrations for language, description, title),
a reusable language-select component, and a track-editor form. Bundle
the self-hosted flag-icons v7.2.3 library and a NAS auto-sync command.

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

app/Console/Commands/NasAutoSync.php

@@ -0,0 +1,75 @@
+<?php
+
+namespace App\Console\Commands;
+
+use App\Jobs\NasSyncVideoJob;
+use App\Models\User;
+use App\Models\Video;
+use App\Services\NasSyncService;
+use Illuminate\Console\Command;
+
+class NasAutoSync extends Command
+{
+    protected $signature   = 'nas:auto-sync';
+    protected $description = 'Push locally-stored files to NAS when NAS is available. Runs as a scheduled task.';
+
+    public function handle(NasSyncService $nas): int
+    {
+        if (! $nas->isEnabled()) {
+            return 0; // NAS down or disabled — nothing to do
+        }
+
+        // Videos whose file OR thumbnail/slides are still on local disk
+        $synced = 0;
+        Video::with(['user', 'slides'])
+            ->where('status', 'ready')
+            ->where('path', 'like', 'users/%')
+            ->get()
+            ->each(function (Video $video) use ($nas, &$synced) {
+                $hasLocalVideo = file_exists(storage_path('app/' . $video->path));
+
+                // Check for locally-stored thumbnail (NAS push failed during edit)
+                $hasLocalThumb = $video->thumbnail
+                    && str_starts_with($video->thumbnail, 'users/')
+                    && file_exists(storage_path('app/' . $video->thumbnail));
+
+                // Check for locally-stored slides
+                $hasLocalSlide = false;
+                foreach ($video->slides as $slide) {
+                    if (str_starts_with($slide->filename, 'users/')
+                        && file_exists(storage_path('app/' . $slide->filename))) {
+                        $hasLocalSlide = true;
+                        break;
+                    }
+                }
+
+                if ($hasLocalVideo || $hasLocalThumb || $hasLocalSlide) {
+                    NasSyncVideoJob::dispatch($video);
+                    $synced++;
+                }
+            });
+
+        // Avatars and banners stuck locally
+        User::whereNotNull('avatar')->orWhereNotNull('banner')->get()
+            ->each(function (User $user) use ($nas) {
+                if ($user->avatar
+                    && str_starts_with($user->avatar, 'users/')
+                    && file_exists(storage_path('app/' . $user->avatar))) {
+                    $nas->syncAvatar($user, storage_path('app/' . $user->avatar));
+                    $nas->deleteLocalAvatar($user);
+                }
+                if ($user->banner
+                    && str_starts_with($user->banner, 'users/')
+                    && file_exists(storage_path('app/' . $user->banner))) {
+                    $nas->syncCover($user, storage_path('app/' . $user->banner));
+                    $nas->deleteLocalBanner($user);
+                }
+            });
+
+        if ($synced > 0) {
+            $this->info("Queued {$synced} video(s) for NAS sync.");
+        }
+
+        return 0;
+    }
+}