Refactor UI assets and harden quality checks

tests/test_settings.py

@@ -0,0 +1,16 @@
+import pytest
+
+from karldns.settings import _is_reserved_admin_path, _validate_launch_secrets
+
+
+def test_reserved_admin_path_matches_exact_and_nested_public_routes() -> None:
+    assert _is_reserved_admin_path("/api")
+    assert _is_reserved_admin_path("/api/v1")
+    assert _is_reserved_admin_path("/logo.png")
+    assert not _is_reserved_admin_path("/ops")
+    assert not _is_reserved_admin_path("/apix")
+
+
+def test_launch_secrets_require_strong_admin_password() -> None:
+    with pytest.raises(RuntimeError, match="DDNS_ADMIN_PASSWORD"):
+        _validate_launch_secrets("short", "")