Messaging · Stickers and GIFs: a sticker picker and a GIF picker

StickerPicker shows stickers a pack at a time, chosen above with a
segmented control; a search spans every pack and keeps the stickers
whose names hold it. Arrows move, Enter or a press picks. It reuses the
glyph grid, now forms::picks, which takes its columns and cell size and
titles from the host, so emoji, icons and stickers share one searchable
grid; forms::glyphs keeps the emoji and icon pickers.

GifPicker packs host GIFs in two columns, each moving, under a search
it owns; the host hears the trimmed words only when they change, and
categories fill the search while it is empty. Waiting, it shows tiles
in GIF shapes; finding nothing, it says so. Each GIF is a Tab stop that
a press, Enter or Space picks.

The share toggle now shows its state, as the microphone and camera do.
The gallery ships line-drawn stickers and small GIFs made from its own
pictures.

src/messaging/mod.rs

@@ -1,5 +1,6 @@
 mod call;
 mod channels;
+mod gifs;
 mod header;
 mod incoming;
 mod members;
@@ -8,6 +9,7 @@ mod people;
 mod pins;
 mod receipt;
 mod status;
+mod stickers;
 mod thread;
 mod tiles;
 
@@ -16,6 +18,7 @@ mod tests;
 
 pub use call::{CallControls, HuddleIndicator, VoiceCallBar};
 pub use channels::{ChannelItem, ChannelList, ChatRow, DirectMessageItem};
+pub use gifs::{Gif, GifPicker, Gifs};
 pub use header::ChannelHeader;
 pub use incoming::IncomingCallDialog;
 pub use members::{Member, MemberList};
@@ -24,5 +27,6 @@ pub use people::{OnlineStatus, UserProfileCard};
 pub use pins::{PinnedMessage, PinnedMessages};
 pub use receipt::{Delivery, ReadReceipt};
 pub use status::{ClearAfter, Status, StatusSetter};
+pub use stickers::{Sticker, StickerPack, StickerPicker};
 pub use thread::{MessageThread, ThreadPanel};
 pub use tiles::{ParticipantTile, ScreenShareView, VideoCallGrid};