nisse-review marks a reply that settles its thread; the PR's author resolves it

The reviewer is read-only (R3), so Gitea refuses it resolving a thread.
Now each reply says whether it settles its thread, and a settled reply
carries <!-- nisse-review: settled -->. nisse-dev, as the author, resolves
every comment on that thread's line when it watches the PR, and doesn't
take the settled reply as a point to answer. scripts/resolve_settled.py
does the same for PRs made by hand.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01J5Utyfzw7gF7UhjRDEtjTk

nisse-review/tests/test_review_stop.py

@@ -94,9 +94,11 @@ def test_stopped_is_no_failure_handlers_would_take() -> None:
 def test_replies_posted_before_a_stop_are_not_posted_again(tmp_path: Path) -> None:
     model = Stopping(
         *REVIEW,
-        [call("reply", point="P1", text="Tabs never occur here.")],
-        [call("reply", point="P2", text="It counts words, yes.")],  # stopped here
-        [call("reply", point="P1", text="It counts words, yes.")],
+        [call("reply", point="P1", text="Tabs never occur here.", settled="no")],
+        [
+            call("reply", point="P2", text="It counts words, yes.", settled="no")
+        ],  # stopped here
+        [call("reply", point="P1", text="It counts words, yes.", settled="no")],
         [call("done")],
         at=5,
     )