Brings the Flutter app's emoji and thread surfaces up to desktop parity.
## Emoji
- **Full emoji-mart dataset** generated from the same `@emoji-mart/data`
set desktop uses (1,870 emoji, 8 categories), committed as an asset — so
shortcodes, names, and keywords are identical across clients. `just
mobile-emoji-data` regenerates it.
- **Rebuilt the tray**: search (a Dart port of desktop's tiered
`emojiSearch` ranking, extended to names and keywords), a
frequently-used section, and one continuous scroll with pinned section
headers. The category rail is a shortcut into that list, not a page
switcher, and spans the full width the search field uses. Custom emoji
share the native glyph size and cell.
- **Reaction pills** match desktop's geometry, and the count shows at 1.
- **Emoji-only messages** render at 36px with 1.45em inline custom
emoji, matching desktop's `emojiOnly` treatment.
- **Positive-emoji burst** ported from desktop's `EmojiBurstProvider`,
suppressed under reduced motion.
## Threads
- **Top-down layout** — head first under the app bar, replies flowing
down, like desktop's thread panel. The old reversed list bottom-anchored
the content and jammed the head against the composer.
- **Tap a channel message to open its thread**; long-press still opens
the action sheet.
- **Live reactions.** The thread's relay query is one-shot and its
`kinds` filter carries only content rows, so a reaction event could not
reach an open thread at all, and `allMessages` was a snapshot frozen
when the route was pushed — a new pill only appeared after leaving and
re-entering, which refetched. The live channel events are now unioned
into the thread's list. The burst is also route-guarded, since the
channel timeline stays mounted underneath and was claiming it first.
- The `+` affordance follows the channel: replies stay bare until they
carry a reaction, and the head keeps a standing `+`.
## Keyboard
A deliberate downward drag past ~48px dismisses the keyboard; short
scrolls leave it alone. Applies to the channel list, the thread list,
and the compose bar (via a raw `Listener`, so it can't steal the field's
tap or selection drags).
True finger-tracking dismissal is out of scope — Flutter only offers
`manual`/`onDrag`, and 1:1 tracking needs a native `UIScrollView` proxy
plus Android's `WindowInsetsAnimationController`.
## Testing
`just mobile-check` and `just mobile-test` pass (965 tests). New
coverage for emoji search ranking, dataset parsing, the emoji-only
predicate, tray scroll/rail behavior, reaction pills and the burst, and
both thread fixes above. `just ci` green.
---------
Signed-off-by: kenny lopez <klopez4212@gmail.com>
Signed-off-by: npub12zsjdqx8dud99s9h47xmk9lq93vryf7zjrae8wdrmma52cg5yglseyulst <50a12680c76f1a52c0b7af8dbb17e02c583227c290fb93b9a3defb456114223f@buzz.block.builderlab.xyz>
Signed-off-by: klopez4212 <klopez4212@gmail.com>
Co-authored-by: npub12zsjdqx8dud99s9h47xmk9lq93vryf7zjrae8wdrmma52cg5yglseyulst <50a12680c76f1a52c0b7af8dbb17e02c583227c290fb93b9a3defb456114223f@buzz.block.builderlab.xyz>
## What
- morph the composer plus button into the attachment menu, camera, and
photo surfaces
- add ordered multi-select with inline recent photos and system picker
fallback
- add native iOS attachment/photo popovers and align the Android camera
treatment
## Stack
- follows #3312
## Validation
- `just mobile-check`
- `flutter test test/features/channels/compose_bar_test.dart`
- full mobile pre-push suite
---------
Signed-off-by: kenny lopez <klopez4212@gmail.com>
