Implement the deferred I1b readline shortcuts in the command input
field (ADR-0049, closing issue #29):
Esc clear a partly-typed command (only when no completion memo)
Ctrl-A cursor to line start (Home alias)
Ctrl-E cursor to line end (End alias)
Ctrl-W delete the previous word (readline-style, UTF-8 safe)
Ctrl-K kill to end of line
Ctrl-U kill to start of line
Esc precedence is preserved: a live Tab-completion memo still wins
(Esc undoes the completion first, ADR-0022); Esc clears only when no
memo is alive. While a sidebar panel is focused (Ctrl-O), Esc exits
navigation mode upstream and never clears the input draft. Cursor-only
keys leave history navigation intact like Home/End; buffer-mutating
keys end it like Backspace.
New helpers clear_input / delete_prev_word / kill_to_end /
kill_to_start in src/app.rs. 22 new Tier-1 tests (2458 pass / 0 fail
/ 0 skip, clippy clean). ADR-0049 amends ADR-0046's OOS list;
requirements.md I1b marked done.
claude@clouddev1