feat: add reconciliation workflow MCP tools for already-landed PRs (Closes #301)

Expose read-only assess/scan tools and capability planning so already-landed
open PRs can be reconciled without review or merge. Register the
gitea-reconcile-landed-pr skill and workflow-source verification.

role_session_router.py

@@ -72,6 +72,8 @@ AUTHOR_TASKS = frozenset({
     "comment_pr",
     "address_pr_change_requests",
     "delete_branch",
+    "reconcile_landed_pr",
+    "reconcile-landed-pr",
 })
 
 TASK_REQUIRED_ROLE = {
@@ -90,6 +92,8 @@ TASK_REQUIRED_ROLE = {
     "blind_pr_queue_review": "reviewer",
     "request_changes_pr": "reviewer",
     "approve_pr": "reviewer",
+    "reconcile_landed_pr": "author",
+    "reconcile-landed-pr": "author",
 }
 
 WRONG_ROLE_REVIEWER_MSG = (