fix(ci): correct issue triage labels and repro detection (#49999)

## Summary of the Pull Request

Fixes two automated issue-triage regressions exposed by #49989:

- Stops `.github/workflows/issue-triage.md` from adding, removing, or
replacing version labels. Reported versions remain available for the
triage summary and update guidance only.
- Expands `.github/scripts/issue-triage/issue-context.py` action
detection so concise natural-language reproduction steps using verbs
such as `make`, `hold`, and `use` are treated as actionable.
- Adds regression coverage for #49989 and a workflow contract test that
prohibits version-label management.

## PR Checklist

- [x] **Communication:** Discussed with a core contributor based on the
automation behavior observed in #49989
- [x] **Tests:** Added/updated and all pass
- [x] **Dev docs:** Updated `.github/scripts/issue-triage/README.md`

## Detailed Description of the Pull Request / Additional comments

The issue body in #49989 was not edited after creation. The workflow
received the original reproduction steps, but deterministic
preprocessing recognized only one action verb (`press`) and classified
the steps as insufficient because two action markers were required. The
publisher then added `Needs-Author-Feedback` from that result.

Independently, the publisher explicitly matched the reported PowerToys
version against repository labels and added `0.100.2`. That
version-label mutation has been removed from both the source workflow
and generated lockfile, with a static contract test to prevent it from
returning.

This PR does not close #49989 because that issue tracks the underlying
Keyboard Manager behavior, not the triage automation regression.

## Validation Steps Performed

- `python -m unittest discover .github\scripts\issue-triage\tests` — all
50 tests passed.
- Evaluated the exact #49989 issue body through `reproduction_quality`;
it now returns `SUFFICIENT`.
- Regenerated `.github/workflows/issue-triage.lock.yml` with `gh aw
compile issue-triage --no-check-update` using gh-aw v0.86.2.

Copilot-Session: 498721d4-1098-4298-ac8a-147066fbfea3

.github/scripts/issue-triage/tests/test_workflow_contract.py

@@ -43,6 +43,15 @@ class WorkflowContractTests(unittest.TestCase):
         ):
             self.assertIn(f"--deny-tool '\\''shell({command})'\\''", generated)
 
+    def test_workflow_never_manages_version_labels(self):
+        source = WORKFLOW_SOURCE.read_text(encoding="utf-8")
+        generated = WORKFLOW_LOCK.read_text(encoding="utf-8")
+
+        for workflow in (source, generated):
+            self.assertNotIn("versionLabels", workflow)
+            self.assertNotIn("desiredVersionLabel", workflow)
+        self.assertRegex(source, r"never adds or removes\s+version labels")
+
 
 if __name__ == "__main__":
     unittest.main()