Add share-video-by-email feature

New POST /videos/{video}/share/email route (auth + throttled) handled by
VideoController@shareByEmail, sending the VideoShared mailable rendered from
emails/video-shared.blade.php. Wired into the share modal and video-actions.

Co-Authored-By: Claude Opus 4.7 <[email protected]>

app/Http/Controllers/VideoController.php

@@ -2176,6 +2176,47 @@ class VideoController extends Controller
         return response()->json(['url' => route('share.access', $token)]);
     }
 
+    /**
+     * Email a friend a properly-formatted share email, version-aware: the link and the
+     * email's title reflect the language track the sender chose. The URL is built
+     * server-side so outgoing mail can never carry an attacker-supplied link.
+     */
+    public function shareByEmail(Request $request, Video $video)
+    {
+        if (! $video->isShareable() || ! $video->canView(Auth::user())) {
+            return response()->json(['error' => 'This video cannot be shared.'], 403);
+        }
+
+        $data = $request->validate([
+            'email'   => 'required|email|max:255',
+            'message' => 'nullable|string|max:500',
+            'track'   => 'nullable|integer',
+        ]);
+
+        $trackId    = (int) ($data['track'] ?? 0);
+        $shareTitle = $video->title;
+        $shareUrl   = $video->share_url;
+        if ($trackId && ($track = $video->audioTracks->firstWhere('id', $trackId))) {
+            if (! empty($track->title)) $shareTitle = $track->title;
+            $shareUrl .= (str_contains($shareUrl, '?') ? '&' : '?') . 'track=' . $trackId;
+        }
+
+        try {
+            \Mail::to($data['email'])->send(new \App\Mail\VideoShared(
+                $video,
+                $shareUrl,
+                Auth::user(),
+                $data['message'] ?? null,
+                $shareTitle,
+            ));
+        } catch (\Throwable $e) {
+            \Log::error('Share-by-email failed: ' . $e->getMessage(), ['video_id' => $video->id]);
+            return response()->json(['error' => 'Could not send the email right now. Please try again.'], 500);
+        }
+
+        return response()->json(['success' => true]);
+    }
+
     public function accessShare(Request $request, string $token)
     {
         $share = \DB::table('video_shares')->where('token', $token)->first();