fix(finishing): name the actual files in the refusal prompt

`git status --porcelain` collapses a wholly-untracked directory to a single
`?? docs/` line. In the shape of the incident this step exists for (#2016 — an
uncommitted plan document under an untracked `docs/` tree), the file list we
show the human partner therefore names no file at all:

    $ git -C "$WORKTREE_PATH" status --porcelain
    ?? docs/
    $ git -C "$WORKTREE_PATH" status --porcelain -uall
    ?? docs/superpowers/plans/2026-08-04-csv-export-rollout.md

Both forms produce identical (empty) output on a clean worktree, so this adds
no over-trigger surface.

Found while running this PR's behavioral micro-tests. Every treatment agent
dug past `?? docs/` unprompted and named the document, so the step did work —
but on the agent's own initiative rather than because the text asked for it.
That initiative is not reliable one tier down: Claude Haiku 4.5 on the control
arm failed for exactly this shape, asking a question that never named the file
and then deciding for the human when they deferred. Nothing in the prior
wording stopped a treatment agent from relaying `?? docs/` verbatim and
satisfying the letter of the instruction.

Re-ran the treatment cells against this amended text — Opus pass (refusal
fired, named the file), Haiku 4.5 pass (named the file) — no regression.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

skills/finishing-a-development-branch/SKILL.md

@@ -180,7 +180,7 @@ or scratch work. Never `--force` on your own initiative. Show your human
 partner what is at stake and ask:
 
 ```bash
-git -C "$WORKTREE_PATH" status --porcelain
+git -C "$WORKTREE_PATH" status --porcelain -uall
 ```
 
 ```