Return 404 for non-numeric like and bookmark IDs

Constrain the likes/{like} and bookmarks/{bookmark} routes to numeric
IDs. Previously a junk URL such as /likes/twcamp^share|twsrc^ios was
passed to route model binding, and Postgres rejected the text-vs-integer
comparison with a QueryException, returning a 500 instead of a 404.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/Feature/BookmarksTest.php

@@ -32,6 +32,13 @@ class BookmarksTest extends TestCase
         $response->assertViewIs('bookmarks.show');
     }
 
+    #[Test]
+    public function non_numeric_bookmark_id_gives_not_found_response(): void
+    {
+        $response = $this->get('/bookmarks/twcamp^share|twsrc^ios');
+        $response->assertNotFound();
+    }
+
     #[Test]
     public function when_bookmark_is_added_using_http_syntax_check_job_to_take_screenshot_is_invoked(): void
     {

tests/Feature/LikesTest.php

@@ -178,4 +178,11 @@ class LikesTest extends TestCase
         $response = $this->get('/likes/202');
         $response->assertNotFound();
     }
+
+    #[Test]
+    public function non_numeric_like_id_gives_not_found_response(): void
+    {
+        $response = $this->get('/likes/twcamp^share|twsrc^ios');
+        $response->assertNotFound();
+    }
 }