JS-031 MED: classify + ignore + `bin/status.js` — file-row parity

The status core: classify worktree vs baseline and emit the status ULOG. Part of JS-027. Method: Issues.

Input

Context

be status heap-merges baseline-tree ⊕ wt-scan ⊕ staged-put ⊕ staged-del per
path → buckets (ok/put/new/mov/pat/mod/del/mis/unk). Output is a ULOG rendered via HUNK — there is NO "rows" type (ROWS was rooted out, BE-007).

Goals

classify.js: heap-merge the 4 streams (abc.index/abc.merge) → one step per
path → bucket; clean verdict is content-confirmed (codec.sha1), not mtime alone.
ignore.js: hierarchical .gitignore matching (cwd→HOME).
bin/status.js: build the status ULOG, render via the JABC HUNK binding, emit the
summary line (cwd-rel ?branch + counts). File-row parity incl. del / new / mov.

Constraints

libdog+abc ONLY (io scan + abc.index + codec + ULOG + HUNK). No subs/ahead-behind yet.

WIP

Design decisions

wt scan = io.readdir({recursive}) + io.stat + ron.of(mtime); baseline tree
via JS-030 readTree (recursive). Bucket logic mirrors sniff status_step.

TODOs

Repro-first (test/bin/): diff jabc bin/status.js vs native be status on
toy repos — clean, modified, new (untracked + staged), deleted, moved. Red→green.
If HUNKu8sFeedRow (ULOG→HUNK) isn't exposed, note a libdog leaf for JS-034.

Blockers

← JS-030.

Outcome

(pending)