Search mode activated by /search <query>. State fields: :search-mode,
:search-query, :search-matches, :search-match-idx. Up/Down arrows
navigate between matches, Enter jumps to current match, Escape exits.
search-highlight wraps matching substrings in **bold** for markdown
rendering. View-chat shows search header bar with match count and
current position.
- channel-tui-state: 4 search state fields in init-state
- channel-tui-main: modified /search handler, search-mode key handlers
(Up/Down/Enter/Escape), 3 new tests (activate, escape, nav)
- channel-tui-view: search-highlight fn, search header bar,
highlighted content in count+render loops
- TUI Main: 97/98 (1 pre-existing flake) View: 29/29
Amr Gharbeia
06aff97b4e