fix(kanban): promote blocked tasks when parent dependencies complete

recompute_ready only scanned 'todo' tasks for promotion, ignoring
'blocked' tasks entirely. When a task was blocked (e.g. by the circuit
breaker) and its parent dependencies later completed, the task stayed
stuck in 'blocked' forever unless manually unblocked.

Now recompute_ready also scans 'blocked' tasks. When all parents are
done/archived, the blocked task is promoted to 'ready' with failure
counters reset — equivalent to an automatic unblock.

Includes a regression test for the blocked-parent-done promotion path.

hermes_cli/kanban_db.py

@@ -1849,21 +1849,32 @@ def recompute_ready(conn: sqlite3.Connection) -> int:
     promoted = 0
     with write_txn(conn):
         todo_rows = conn.execute(
-            "SELECT id FROM tasks WHERE status = 'todo'"
+            "SELECT id, status FROM tasks WHERE status IN ('todo', 'blocked')"
         ).fetchall()
         for row in todo_rows:
             task_id = row["id"]
+            cur_status = row["status"]
             parents = conn.execute(
                 "SELECT t.status FROM tasks t "
                 "JOIN task_links l ON l.parent_id = t.id "
                 "WHERE l.child_id = ?",
                 (task_id,),
             ).fetchall()
-            if all(p["status"] in {"done", "archived"} for p in parents):
-                conn.execute(
-                    "UPDATE tasks SET status = 'ready' WHERE id = ? AND status = 'todo'",
-                    (task_id,),
-                )
+            if all(p["status"] in ("done", "archived") for p in parents):
+                # Blocked tasks also get their failure counters reset —
+                # this is effectively an auto-unblock.
+                if cur_status == "blocked":
+                    conn.execute(
+                        "UPDATE tasks SET status = 'ready', "
+                        "consecutive_failures = 0, last_failure_error = NULL "
+                        "WHERE id = ? AND status = 'blocked'",
+                        (task_id,),
+                    )
+                else:
+                    conn.execute(
+                        "UPDATE tasks SET status = 'ready' WHERE id = ? AND status = 'todo'",
+                        (task_id,),
+                    )
                 _append_event(conn, task_id, "promoted", None)
                 promoted += 1
     return promoted
@@ -3554,6 +3565,17 @@ def set_max_runtime(
     return cur.rowcount == 1
 
 
+def _error_fingerprint(error_text: str) -> str:
+    """Normalize an error message for grouping identical failures.
+
+    Strips host-specific details (PIDs, timestamps) so that errors
+    with the same root cause produce the same fingerprint.
+    """
+    fp = re.sub(r'\bpid \d+\b', 'pid N', error_text[:80])
+    fp = re.sub(r'\b\d{10,}\b', '<TS>', fp)
+    return fp.lower().strip()
+
+
 def detect_crashed_workers(conn: sqlite3.Connection) -> list[str]:
     """Reclaim ``running`` tasks whose worker PID is no longer alive.
 

tests/hermes_cli/test_kanban_db.py

@@ -134,6 +134,34 @@ def test_recompute_ready_cascades_through_chain(kanban_home):
         assert kb.get_task(conn, c).status == "ready"
 
 
+def test_recompute_ready_promotes_blocked_with_done_parents(kanban_home):
+    """blocked tasks with all parents done should be promoted to ready."""
+    with kb.connect() as conn:
+        parent = kb.create_task(conn, title="parent", assignee="a")
+        child = kb.create_task(
+            conn, title="child", assignee="a", parents=[parent],
+        )
+        # Complete the parent
+        kb.claim_task(conn, parent)
+        kb.complete_task(conn, parent, result="ok")
+        # Manually block the child (simulates a worker that failed
+        # after the parent finished)
+        conn.execute(
+            "UPDATE tasks SET status='blocked', consecutive_failures=5, "
+            "last_failure_error='persistent error' WHERE id=?",
+            (child,),
+        )
+        conn.commit()
+        assert kb.get_task(conn, child).status == "blocked"
+        # recompute_ready should promote blocked → ready and reset failures
+        promoted = kb.recompute_ready(conn)
+        assert promoted == 1
+        task = kb.get_task(conn, child)
+        assert task.status == "ready"
+        assert task.consecutive_failures == 0
+        assert task.last_failure_error is None
+
+
 def test_recompute_ready_fan_in_waits_for_all_parents(kanban_home):
     with kb.connect() as conn:
         a = kb.create_task(conn, title="a")