Enforce issue-write tool gates to match task capability resolver (Issue #69)

Extract TASK_CAPABILITY_MAP into task_capability_map.py as the single source
of truth shared by gitea_resolve_task_capability and issue-mutating tools.
Gate gitea_create_issue, gitea_close_issue, gitea_mark_issue, and
gitea_set_issue_labels with structured #142 permission reports. Add regression
tests proving resolver-denied tasks fail closed at the raw tool layer.

Implements mcp-control-plane #69.

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

tests/test_audit.py

@@ -162,7 +162,8 @@ class _AuditWiringBase(unittest.TestCase):
     def _env(self, **extra):
         env = {"GITEA_AUDIT_LOG": self.audit_path,
                "GITEA_PROFILE_NAME": "gitea-author",
-               "GITEA_ALLOWED_OPERATIONS": "read,merge"}
+               "GITEA_ALLOWED_OPERATIONS": (
+                   "read,merge,gitea.issue.create,gitea.issue.close")}
         env.update(extra)
         return env
 
@@ -237,7 +238,10 @@ class TestSimpleToolAudit(_AuditWiringBase):
     def test_disabled_writes_nothing_and_no_extra_call(self, _auth, _get_all, mock_api, _role):
         # No GITEA_AUDIT_LOG -> audit is a no-op: one create POST, no file.
         mock_api.return_value = {"number": 1, "html_url": "http://x/1"}
-        with patch.dict(os.environ, {"GITEA_PROFILE_NAME": "gitea-author"}, clear=True):
+        with patch.dict(os.environ, {
+            "GITEA_PROFILE_NAME": "gitea-author",
+            "GITEA_ALLOWED_OPERATIONS": "gitea.issue.create",
+        }, clear=True):
             gitea_create_issue(title="x", remote="prgs")
         issue_posts = [
             c for c in mock_api.call_args_list if c.args[0] == "POST"