Redirect legacy /q/* URLs to canonical ladl.link addresses.

External /q requests 301/307 to ladl.link; internal X-Ladill-Internal requests still serve content for platform proxying.

Co-authored-by: Cursor <cursoragent@cursor.com>

app/Services/Link/LinkPlatformProxy.php

@@ -57,15 +57,13 @@ class LinkPlatformProxy
     /** @return array<string, string> */
     private function forwardHeaders(Request $request): array
     {
-        $headers = [];
-        foreach (['Accept', 'Accept-Language', 'User-Agent', 'Referer'] as $name) {
-            $value = $request->header($name);
-            if ($value !== null) {
-                $headers[$name] = $value;
-            }
-        }
-
-        return $headers;
+        return array_filter([
+            'Accept' => $request->header('Accept'),
+            'Accept-Language' => $request->header('Accept-Language'),
+            'User-Agent' => $request->header('User-Agent'),
+            'Referer' => $request->header('Referer'),
+            'X-Ladill-Internal' => '1',
+        ]);
     }
 
     /** @param array<string, array<int, string>> $headers */