fix(#2415): close_phase_todos stages the pending/ deletion alongside completed/ (#2447)

* fix(#2415): close_phase_todos stages the pending/ deletion alongside completed/

Bug: the workflow step moved resolved todos from .planning/todos/pending/
to .planning/todos/completed/ with a plain 'mv', then committed listing
ONLY the destination directory in --files:

    mv "$TODO_FILE" "$COMPLETED_DIR/"
    gsd_run query commit '...' --files .planning/todos/completed/ .planning/STATE.md

Git's index still tracked the moved file at its old pending/<name>.md path.
The commit therefore only staged the new completed/<name>.md copy — the
deletion at pending/ was never staged, never committed, and lingered as an
unstaged deletion in git status indefinitely until some later broad
'git add -A' caught it. The phase genuinely closed the todo, but the
working tree was never clean.

Fix: add .planning/todos/pending/ to the --files list. 'git add' of that
directory (since git 2.0) stages deletions of tracked files in the pathspec,
so the moved-away file is staged as a deletion atomically with the new
completed/ copy in the same commit.

Chose plain mv + two-dir --files over 'git mv' because git mv FAILS on:
  - untracked todos (new todo file not yet committed)
  - non-git .planning dirs (worktree safety / pre-init projects)
Plain mv has neither failure mode.

Regression tests in tests/close-phase-todos-stage-deletion.test.cjs
(source-text-is-the-product: workflow .md text IS what the runtime loads)
cover:
  - the commit --files list includes BOTH completed/ AND pending/
  - the move uses plain 'mv' (not 'git mv') so untracked + non-git cases work

* chore(#2415): trim commit subject to keep execute-phase.md under byte ceiling

The fix added '.planning/todos/pending/' (~26 bytes) to the commit --files
list. To stay under the ADR-857 Phase 6 pre-phase-6 byte ceiling margin
(93400 bytes, hard ceiling 93600), shortened the commit subject from
'auto-close N todo(s) resolved by this phase' to 'close N resolved todo(s)'.
Net change vs origin/next: +6 bytes (93384 → 93390), well under the margin.

Also regenerates the golden-install-parity fixtures (execute-phase.md
content-hash update across all runtimes).

* chore(#2415): bump execute-phase.md workflow-size baseline (93384 → 93390)

The +pending/ fix added 6 net bytes (93384 → 93390), still well under the
ADR-857 Phase 6 pre-phase-6 byte ceiling margin (93400).

* chore(changeset): backfill pr:2447 in .changeset/sturdy-wasps-run.md

* fix(#2415): add issue ref to allow-test-rule annotation (ADR-456)

CI lint-allow-test-rule-refs failed on the prior commit — ADR-456 requires
'// allow-test-rule: <category> see #NNNN' so every exemption is traceable
to an issue. Added 'see #2415' to the source-text-is-the-product annotation.

.changeset/sturdy-wasps-run.md

@@ -0,0 +1,5 @@
+---
+type: Fixed
+pr: 2447
+---
+**`close_phase_todos` no longer leaves moved todos as phantom unstaged deletions in `git status`** — the workflow step moved resolved todos from `.planning/todos/pending/` to `.planning/todos/completed/` with a plain `mv`, then committed by listing only the destination directory in `--files`. Git's index still tracked the moved file at its old `pending/` path, so the deletion was never staged and the moved-away file lingered as an unstaged deletion in `git status` until some later broad `git add -A` happened to catch it. The step's commit `--files` list now includes BOTH directories so `git add .planning/todos/pending/` stages the deletion atomically with the new `completed/` copy in the same commit. (#2415)