LibURL/Pattern: Add a representation of a URL Pattern

This is the core object behind a URL pattern which when constructed
can be used for matching the pattern against URLs.

However, the implementation here is missing key functions such as
the constructor and the 'test'/'exec' functions as that relies on
a significant amount of supporting URLPattern infrastructure such
as two different parsers and a tokenizer.

However, this is enough for us to implement some more of the IDL
wrapper layer of this specification.

Libraries/LibURL/Pattern/Pattern.cpp

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2025, Shannon Booth <shannon@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <LibURL/Pattern/Pattern.h>
+
+namespace URL::Pattern {
+
+// https://urlpattern.spec.whatwg.org/#url-pattern-has-regexp-groups
+bool Pattern::has_regexp_groups() const
+{
+    // 1. If urlPattern’s protocol component has regexp groups is true, then return true.
+    if (m_protocol_component.has_regexp_groups)
+        return true;
+
+    // 2. If urlPattern’s username component has regexp groups is true, then return true.
+    if (m_username_component.has_regexp_groups)
+        return true;
+
+    // 3. If urlPattern’s password component has regexp groups is true, then return true.
+    if (m_password_component.has_regexp_groups)
+        return true;
+
+    // 4. If urlPattern’s hostname component has regexp groups is true, then return true.
+    if (m_hostname_component.has_regexp_groups)
+        return true;
+
+    // 5. If urlPattern’s port component has regexp groups is true, then return true.
+    if (m_port_component.has_regexp_groups)
+        return true;
+
+    // 6. If urlPattern’s pathname component has regexp groups is true, then return true.
+    if (m_pathname_component.has_regexp_groups)
+        return true;
+
+    // 7. If urlPattern’s search component has regexp groups is true, then return true.
+    if (m_search_component.has_regexp_groups)
+        return true;
+
+    // 8. If urlPattern’s hash component has regexp groups is true, then return true.
+    if (m_hash_component.has_regexp_groups)
+        return true;
+
+    // 9. Return false.
+    return false;
+}
+
+}