test: protect planning readiness gate

tests/test_task_breakdown_policy.py

@@ -21,6 +21,7 @@ def policy_failures(section: str, approval_rule: str) -> list[str]:
         "dependencies": r"(?m)^4\. encode acyclic within-Feature sequencing and require every entry Task to depend on all terminal Tasks of every prerequisite Feature;$",
         "contract": r"(?m)^5\. give each Task one specific outcome, repository/component owner, canonical/display identity, task-specific implementation artifacts, concrete inputs and outputs, failure boundaries, exclusions, verification steps, and future acceptance-evidence requirements;$",
         "separate-gates": r"(?m)^6\. keep draft Tasks separate from implementation approval and Kanban Focus admission\.$",
+        "planning-readiness": r"(?m)^Architecture must not report planning readiness while any Feature allocated to the release lacks this complete Task breakdown\. A Feature-shaped placeholder Task, a generated empty Task group, or requirement coverage without executable Tasks does not satisfy the gate\.$",
         "protected-history": r"(?m)^Approved, Kanban-admitted, in-progress, or completed Tasks must not be deleted or silently rewritten\. Retain an obsolete Task with a terminal Superseded or Cancelled status, its prior evidence and history, and explicit replacement links\.$",
         "approval-invalidation": approval_rule,
     }
@@ -44,6 +45,8 @@ class TaskBreakdownPolicyTest(unittest.TestCase):
         self.assertTrue(policy_failures(f"<!--{self.task_section}-->", self.approval_rule))
         mutations = {
             "draft-protection": ("with no implementation approval, Kanban admission, execution, or completion evidence", "even with implementation approval, Kanban admission, execution, or completion evidence"),
+            "planning-readiness": ("must not report planning readiness", "may report planning readiness"),
+            "placeholder-rejection": ("A Feature-shaped placeholder Task, a generated empty Task group, or requirement coverage without executable Tasks does not satisfy the gate.", ""),
             "cardinality": ("between two and six", "at least two"),
             "mapping": ("exactly, and reciprocally", "loosely"),
             "dependencies": ("all terminal Tasks", "some Tasks"),