fix: prepare writable data mount in installer

tests/test_install_script.py

@@ -48,3 +48,15 @@ def test_shell_installer_supports_legacy_tgshop_volume_and_dsn_paths():
     assert "remnawave-minishop-db-data" in script
     assert "pg_dump --clean --if-exists" in script
     assert "run_compose run --rm migrate" in script
+
+
+def test_shell_installer_only_prepares_data_mount_not_runtime_content():
+    script = INSTALL_SCRIPT.read_text(encoding="utf-8")
+
+    assert 'data_dir="$TARGET_DIR/data"' in script
+    assert "mkdir -p \"$data_dir\"" in script
+    assert "chown \"$APP_UID:$APP_GID\" \"$data_dir\"" in script
+    assert "data_dir/themes" not in script
+    assert "webapp-logo" not in script
+    assert "webapp-emoji" not in script
+    assert "locales-overrides.json" not in script