fix: settings dropdowns, background animations, ringing, avatar decorations

Settings dropdowns (Bug #3):
- Add reusable SettingsSelect component using Menu+PopOut+FocusTrap — exact
  same pattern as Message Layout, so all dropdowns look consistent
- Replace raw <select> for Seasonal Theme, UI Font, AFK Timeout, and
  Join & Leave Sounds with SettingsSelect

Animated chat backgrounds bleeding onto content (Bug #6 / #7):
- Remove filter:brightness() and opacity animations from chatBackground.ts
  (animRainGlowKeyframe, animGridBrightnessKeyframe, animFirefliesGlowKeyframe,
  animFirefliesBlinkKeyframe). These were applied to the Page element which
  caused ALL descendants (messages, composer) to flash in sync.
  Also created a CSS stacking context on Page that pushed SeasonalEffect
  (position:fixed; z-index:9997) behind the animated background layer.
- Only backgroundPosition / backgroundSize animations remain — safe, do not
  affect descendants, and do not create stacking contexts.
- Remove now-unused animation keyframe imports from chatBackground.ts.

Voice ringing in persistent rooms (Bug #5):
- Narrow the ringing condition from (Invite|Knock|Restricted) to only Invite,
  matching exactly the rooms where the call button is visible.
- Add room.isCallRoom() early-exit so m.join_rule:call rooms never ring.

Avatar decoration images not loading (Bug #8):
- Change loading="lazy" → loading="eager" in DecorationPreviewCell.
  Lazy loading does not reliably trigger for images inside nested overflow
  scroll containers (the settings panel scroll area), so images never loaded.

Docs: LOTUS_BUGS.md updated with root cause and resolution for all 5 new bugs.
Docs: LOTUS_TODO.md adds P5-35/P5-36 (deferred desktop notification/jump list).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

LOTUS_TODO.md

@@ -363,6 +363,24 @@ Themes:
 
 ---
 
+### [ ] P5-35 · Desktop — Notification Click Opens Room (DEFERRED)
+
+**What:** Clicking a system tray notification navigates to the relevant room. Quick-reply from the notification toast would send the reply without opening the window.  
+**Status:** Deferred — `tauri-plugin-notification` has no Rust click/action callback API. Quick-reply would need a custom WinRT toast activator + COM registration, which can't be compile-tested without a Windows build environment.  
+**Note:** Tray icon and `matrix:` deep links already bring the window forward on most interactions. Revisit when tauri-plugin-notification gains click handler support upstream.  
+**Complexity:** High (platform-specific native code required).
+
+---
+
+### [ ] P5-36 · Desktop — Windows Jump List (DEFERRED)
+
+**What:** Right-clicking the taskbar icon shows a jump list with recent/favorite rooms for quick navigation.  
+**Status:** Deferred — implementing the Windows COM jump list API in Tauri requires iterating on C++/COM code that can only be compile-checked on Windows, making blind CI iteration impractical.  
+**Action when unblocked:** Revisit when a Tauri plugin abstracts the Windows Shell `ICustomDestinationList` interface, or when a Windows build environment is available for local iteration.  
+**Complexity:** High (Windows-only native COM).
+
+---
+
 ## Blocked Features
 
 These features are confirmed desirable but cannot be built until the listed dependency is resolved.