Typing `@` in the compose box opens a dropdown of matching mesh
members fed by /v1/members. Filters live by displayName prefix
(case-insensitive); online members rank above offline; shorter
names rank higher; capped at 8 entries.
Keyboard: ArrowUp/Down to navigate, Enter or Tab to insert,
Escape to dismiss. Mouse hover updates the selection; mousedown
inserts (mousedown so the textarea doesn't lose focus first).
Rendered messages now highlight @mentions in clay so they're
visually distinct from plain text — same regex the autocomplete
uses, so the round trip is consistent.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
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