Replace the leftover 'subfeed' name across logger names + log_config,
frontend localStorage keys, Postgres user/db/volume defaults in the
compose files, .env.example, config.py, backup/restore scripts and the
README. Pure rename; no behavioural change. localStorage keys move from
subfeed.* to siftlode.* (one-time UI-state reset is acceptable).
- Add a theme-aware glass surface system (.glass/.glass-card + ambient backdrop,
performance-mode opt-out) and apply it across panels, popovers, toasts, cards,
sidebar widgets, channel rows, video cards and login.
- SettingsPanel: slide in/out animation, glass styling, wrapping pill tabs (no
horizontal scrollbar) with a prominent active state.
- Notifications: auto-dismiss can be switched off (stays until closed); the test
notification now also triggers the alert sound; resume a suspended AudioContext.
- Add an app-wide, toggleable hint/tooltip system (lib/hints + Tooltip) and wire
hints across the settings and channel-manager surfaces; persisted per account.
