chore(skills): git-commit — triage pre-existing changes before committing

Add a mandatory step between assessing changes and grouping commits:
surface any modified/untracked files that weren't touched in the current
session and ask the user whether to include them.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.claude/skills/git-commit/SKILL.md

@@ -14,16 +14,31 @@ allowed-tools: Bash, Read, Grep, Glob, Write, Edit
 ## Workflow
 
 1. Run `git status` and `git diff --stat` to assess all pending changes.
-2. Group changes into **logical commits** — each commit should represent one
+2. **Triage: session vs pre-existing.** Separate changes you made in this
+   session from changes that were already dirty when the session started.
+   Check the conversation history — if you didn't touch a file, it's
+   pre-existing. After grouping your own commits, surface any remaining
+   modified or untracked files to the user:
+
+   > These files are also modified/untracked but weren't part of this
+   > session's work:
+   > - `path/to/file` — <brief description of the diff>
+   > - `path/to/other` — <untracked, N files>
+   >
+   > Should any of these be included in a commit?
+
+   Wait for the user's answer before staging them. Never silently skip
+   or silently include pre-existing changes.
+3. Group changes into **logical commits** — each commit should represent one
    coherent change. Common groupings:
    - A bug fix (all files touched to fix one issue)
    - A new feature or system (e.g., new trait files + localization + events)
    - Refactoring / cleanup (encoding fixes, comment fixes, renaming)
    - Config / meta changes (CLAUDE.md, .claude/ skills, mod descriptor)
    - Data corrections (province remapping, missing fields)
-3. For each logical group, stage only the relevant files and commit with a
+4. For each logical group, stage only the relevant files and commit with a
    properly formatted message.
-4. After all commits, update CHANGELOG.md.
+5. After all commits, update CHANGELOG.md.
 
 ## Commit Message Format