- Switched back to custom window management, taking another stab

- Refactored lang yet again, `fennec/lang` is now C++ language. `fennec/string` `fennec/filesystem` and `fennec/format` are now independent.

test/tests/lang/test_sequences.h

@@ -0,0 +1,38 @@
+// =====================================================================================================================
+//  fennec, a free and open source game engine
+//  Copyright © 2025  Medusa Slockbower
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <https://www.gnu.org/licenses/>.
+// =====================================================================================================================
+
+#ifndef FENNEC_TEST_LANG_SEQUENCES_H
+#define FENNEC_TEST_LANG_SEQUENCES_H
+
+#include <fennec/lang/const_sequences.h>
+
+namespace fennec::test
+{
+
+	inline void test_sequences()
+	{
+		static_assert(fennec::is_same_v<make_index_sequence_t<2>, const_index_sequence<0, 1>>);
+		static_assert(fennec::is_same_v<make_index_sequence_t<3>, const_index_sequence<0, 1, 2>>);
+		static_assert(fennec::is_same_v<make_index_sequence_t<4>, const_index_sequence<0, 1, 2, 3>>);
+
+		// TODO
+	}
+
+}
+
+#endif // FENNEC_TEST_LANG_SEQUENCES_H