feat(web): Core Refactor Phase A — extract sampling and cache modules; add adaptive TTL + eviction heuristics, Redis PoC, and metrics wiring. Tests added for TTL, eviction, exports, splash-adaptive, card index, and service worker. Docs+roadmap updated.

code/tests/test_service_worker_offline.py

@@ -0,0 +1,34 @@
+import os
+import importlib
+import types
+import pytest
+from starlette.testclient import TestClient
+
+fastapi = pytest.importorskip("fastapi")  # skip if FastAPI missing
+
+
+def load_app_with_env(**env: str) -> types.ModuleType:
+    for k, v in env.items():
+        os.environ[k] = v
+    import code.web.app as app_module  # type: ignore
+    importlib.reload(app_module)
+    return app_module
+
+
+def test_catalog_hash_exposed_in_template():
+    app_module = load_app_with_env(ENABLE_PWA="1")
+    client = TestClient(app_module.app)
+    r = client.get("/themes/")  # picker page should exist
+    assert r.status_code == 200
+    body = r.text
+    # catalog_hash may be 'dev' if not present, ensure variable substituted in SW registration block
+    assert "serviceWorker" in body
+    assert "sw.js?v=" in body
+
+
+def test_sw_js_served_and_version_param_cache_headers():
+    app_module = load_app_with_env(ENABLE_PWA="1")
+    client = TestClient(app_module.app)
+    r = client.get("/static/sw.js?v=testhash123")
+    assert r.status_code == 200
+    assert "Service Worker" in r.text