feat: Remind Me Later, mobile bookmarks, bug fixes, and doc cleanup

Features:
- Remind Me Later: message context menu item opens a preset time picker
  (20 min / 1 hr / 3 hr / tomorrow 9am); reminders persist to Matrix
  account data (io.lotus.reminders); ReminderMonitor fires a Lotus Toast
  when due, checks every 30s and on tab focus
- Mobile Bookmarks: BookmarksPanel now renders on all screen sizes;
  passes isMobile prop for full-screen absolute overlay on mobile

Bug fixes:
- usePan.ts: memory leak from stale closure in document listener cleanup
- EventReaders.tsx: replace hardcoded hex colors with TDS CSS variables
- CallControls.tsx: replace hardcoded hex colors with TDS CSS variables
- CustomHtml.css.ts: replace hardcoded yellow/black highlight with theme tokens

Docs:
- LOTUS_TODO.md: restore deleted content (Confirmed facts table, Pending
  Audits, P5-30 completed status, full feature descriptions), keep new
  additions (P4-7/8/9, P5-41–57, Implementation Reference), eliminate
  duplicate sections
- LOTUS_BUGS.md: merge RESILIENCE_AUDIT.md findings into Architectural &
  Resilience Audit table; delete RESILIENCE_AUDIT.md
- Remove stale LOTUS_DENOISE_ENGINEERING_REVIEW.md and LOTUS_TODO_REFERENCE.md

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

src/app/features/call/CallControls.tsx

@@ -246,8 +246,8 @@ export function CallControls({ callEmbed }: CallControlsProps) {
               top: '-2.5rem',
               left: '50%',
               transform: 'translateX(-50%)',
-              background: pttActive ? 'rgba(0,255,136,0.18)' : 'rgba(255,107,0,0.12)',
-              border: `1px solid ${pttActive ? 'rgba(0,255,136,0.55)' : 'rgba(255,107,0,0.35)'}`,
+              background: pttActive ? 'var(--lt-accent-green-dim)' : 'var(--lt-accent-orange-dim)',
+              border: `1px solid ${pttActive ? 'var(--lt-accent-green-border)' : 'var(--lt-accent-orange-border)'}`,
               borderRadius: '99px',
               padding: '0.2rem 0.9rem',
               pointerEvents: 'none',
@@ -257,7 +257,7 @@ export function CallControls({ callEmbed }: CallControlsProps) {
             <Text
               size="T200"
               style={{
-                color: pttActive ? '#00FF88' : '#FF6B00',
+                color: pttActive ? 'var(--lt-accent-green)' : 'var(--lt-accent-orange)',
                 fontWeight: 700,
                 letterSpacing: '0.08em',
                 fontFamily: 'JetBrains Mono, monospace',