feat: block manual issue-lock seeding and require lock disclosure (#447)

Add lock_provenance metadata on gitea_lock_issue writes and fail closed at
gitea_create_pr when provenance is missing. Final-report validation now
requires explicit External-state mutations disclosure for issue-lock
read/write/delete and blocks mixed author PR creation with reviewer approval.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

tests/test_commit_payloads.py

@@ -67,6 +67,15 @@ class TestCommitPayloads(unittest.TestCase):
         self.locked_worktree_path = os.path.realpath(self.locked_worktree_dir.name)
 
         self.lock_file_path = "/tmp/gitea_issue_lock.json"
+        import issue_lock_provenance
+
+        work_lease = {
+            "operation_type": "author_issue_work",
+            "issue_number": 263,
+            "branch": "feat/issue-263-native-commit-payloads",
+            "claimant": {"username": "test-user", "profile": "test-author"},
+            "expires_at": "2999-01-01T00:00:00Z",
+        }
         self.lock_data = {
             "issue_number": 263,
             "branch_name": "feat/issue-263-native-commit-payloads",
@@ -74,6 +83,11 @@ class TestCommitPayloads(unittest.TestCase):
             "org": "Example-Org",
             "repo": "Example-Repo",
             "worktree_path": self.locked_worktree_path,
+            "work_lease": work_lease,
+            "lock_provenance": issue_lock_provenance.build_sanctioned_lock_provenance(
+                tool="gitea_lock_issue",
+                claimant=work_lease.get("claimant"),
+            ),
         }
         with open(self.lock_file_path, "w", encoding="utf-8") as fh:
             fh.write(json.dumps(self.lock_data))