Move provider normalization logic into a dedicated module to ensure consistent
handling of provider defaults and user preference inheritance across client and
server. Update layout components to mount ConfigProvider only at the shared
layout level, preventing unnecessary remounts and hydration issues during
navigation. Adjust app config defaults so user provider settings are empty by
default, always inheriting the admin-configured provider unless explicitly set.
Add tests for normalization and sync logic to ensure robust provider resolution.
Integrate changelog version check on settings open, triggering the changelog
panel when a new app version is detected. Refactor user preferences storage to
support metadata via payload utilities, enabling version tracking and future
extensibility. Add API endpoint for changelog version check and related tests
for changelog and preferences payload logic.
