feat(mobile): Wave 4 — RegisterPage responsive + TransferIndicator on settings + MessageInput sheets
- RegisterPage: scroll envelope, iOS-zoom-safe inputs, ≥44px tap targets, mobile-friendly invite chip + swatch row
- TransferIndicator: mounted via MobileScreenHeader.rightActions across every settings/instance screen and inline in MobileChatScreen; touch-close listener; viewport-safe panel width
- MessageInput popovers (emoji/GIF/mention) now route through new InputPopover wrapper — desktop popover, mobile bottom-sheet
- EmojiPicker mobile branch: dynamicWidth + scoped CSS (.emoji-picker-wrapper--mobile) so the <em-emoji-picker> custom element fills the sheet; bigger touch targets (perLine 8, button 40, emoji 28); desktop unchanged
- MessageInput trigger row: mobile-first sizing with md: desktop overrides (40×40 buttons + gap on mobile, 34×34 unchanged on desktop)
- Spec updates: docs/systems/auth.md (RegisterPage responsive contract), docs/systems/uploads.md (TransferIndicator mobile surfaces)
Jannis Braun
fb9fe326c4