feat(tasks): task-content guardrails — structured plans + constraints split (#328)

* feat(tasks): task-content guardrails — structured plans + constraints split

Bound task PLANNING content the way journals/notes already are, fixing the
poor task quality flagged 2026-07-07 (degenerate roots, over-decomposed
leaves, descriptions bloated by an auto-attached conventions dump).

Phase A — plan/AC guardrails (no migration):
- _pm_sub_tasks_gate: cap sub_tasks at 7; per-subtask ceilings (title <=200,
  description <=600) enforced at both the Pydantic boundary and the gate.
  Dropped the min-2-roots and no-subtasks-on-code rules: both contradict the
  2026-05-08 rule (test_cell_pm_can_plan_code_typed_parent_via_i_will_plan)
  and break legitimate single-cell roots. Long comment in the gate explains.
- IWillPlanRequest: plan <=2000, approach <=800 (floor 150 kept), typed
  SubTaskCreate/RiskCreate/OpenQuestionCreate replacing loose list[dict].
- DelegateRequest + task_completeness: acceptance_criteria capped at 7 items,
  each <=200 chars. New FieldRule.MAX_LENGTH_LIST + _post_rule_reject helper
  (extracted to keep the gate under xenon B).
- Routes dump typed models to dicts for the existing rich_plan shaper.

Phase B — conventions split (migration 068):
- New nullable tasks.constraints Text column; _attach_baseline_constraints
  now writes the ## Constraints block there instead of appending to
  description, so description is the human-authored instruction only. The
  conventions still reach the agent independently at spawn via the ambient
  block, so agent correctness is unaffected.
- TaskResponse / Task model / panel Task type carry constraints; panel shows
  a read-only Constraints card. Field is optional on the TS type (backend
  returns null for flag-off / pre-migration rows).

Tests: 5 new gate unit tests, 7 schema tests, 3 AC policy tests, 3 e2e smoke
scenarios; 4 baseline-constraints integration tests updated. ruff/mypy/xenon
clean; 10026 unit+foundation+e2e green; panel typecheck clean.

Refs: plan breezy-imagining-kahn

* test(tasks): use typed SubTaskCreate instead of dict literals in plan tests

make quality runs mypy over tests/ (1079 files), not just roboco/ — the
four sites passing dict literals to the now-typed sub_tasks: list[SubTaskCreate]
field failed mypy. Construct SubTaskCreate directly; the typed model raising
ValidationError IS the boundary the rejection tests assert.

* fix(deps): drop unused python-jose — clears PYSEC-2026-1325 (ecdsa, no fix)

CI's pip-audit went red on a freshly-published advisory PYSEC-2026-1325
against ecdsa 0.19.2 (no fix published — 0.19.2 is the latest). ecdsa is a
transitive dep of python-jose, which is a DIRECT dep of roboco but is NOT
imported anywhere in roboco/ or tests/ (grep-verified). The actual JWT path
uses PyJWT (import jwt) + fastapi_users.jwt, not python-jose.

So python-jose is a dead dependency. Removing it (deletion over an
--ignore-vuln waiver) drops ecdsa + rsa + pyasn1 + their type stubs from the
lockfile, eliminating the CVE at the source. deptry roboco/ stays clean
(no missing-dep), mypy clean, auth + schema tests pass.

Master CI was green 9h before this PR's run, so the advisory published in
that window would red any run including master — this fix unblocks both.

* chore(prompts): regenerate verb tables for typed plan sub_tasks

Phase A's IWillPlanRequest schema change (sub_tasks/risks/open_questions from
loose list[dict] to typed SubTaskCreate/RiskCreate/OpenQuestionCreate) made
the auto-generated verb tables stale. Regenerated via
scripts/regenerate_verb_tables.py — the diff is purely the signature
reflection (list[str|str] -> list[SubTaskCreate], etc.). Required by the
foundation-check gate (Makefile:559).

---------

Co-authored-by: Renn F <rennf93@users.noreply.github.com>

tests/unit/api/routes/v1/test_i_will_plan_rich_required.py

@@ -13,7 +13,7 @@ from fastapi import FastAPI
 from fastapi.testclient import TestClient
 from roboco.api.deps import get_choreographer
 from roboco.api.routes.v1.flow_main_pm import router
-from roboco.api.schemas.v1.flow import IWillPlanRequest
+from roboco.api.schemas.v1.flow import IWillPlanRequest, SubTaskCreate
 
 _AGENT_ID = "00000000-0000-0000-0004-000000000001"
 _HEADERS = {"X-Agent-ID": _AGENT_ID, "X-Agent-Role": "main_pm"}
@@ -111,7 +111,9 @@ def test_i_will_plan_schema_accepts_rich_plan() -> None:
         task_id=uuid4(),
         plan="Route to backend",
         approach=_GOOD_APPROACH,
-        sub_tasks=[{"title": "Backend slice", "description": _GOOD_SUBTASK_DESC}],
+        sub_tasks=[
+            SubTaskCreate(title="Backend slice", description=_GOOD_SUBTASK_DESC)
+        ],
         risks=[],
         open_questions=[],
     )

tests/unit/api/test_schemas_v1_flow.py

@@ -11,6 +11,7 @@ from roboco.api.schemas.v1.flow import (
     DelegateRequest,
     IWillPlanRequest,
     IWillWorkOnRequest,
+    SubTaskCreate,
 )
 from roboco.models.base import Complexity
 
@@ -146,3 +147,101 @@ def test_strlist_drops_non_string_junk_instead_of_crashing() -> None:
         technical_considerations=technical_considerations,
     )
     assert req.technical_considerations == ["real note"]
+
+
+# ---------------------------------------------------------------------------
+# Task-content guardrails (2026-07-07): ceilings on plan content + AC caps.
+# ---------------------------------------------------------------------------
+
+
+def test_i_will_plan_request_rejects_overlong_plan() -> None:
+    """plan >2000 chars is rejected at the boundary — the bloat defect."""
+    with pytest.raises(ValidationError) as exc:
+        IWillPlanRequest(
+            task_id=uuid4(),
+            plan="x" * 2001,
+            approach="a" * 150,
+        )
+    assert "plan" in str(exc.value)
+
+
+def test_i_will_plan_request_rejects_overlong_approach() -> None:
+    """approach >800 chars is rejected — no ceiling was the bloat bug."""
+    with pytest.raises(ValidationError) as exc:
+        IWillPlanRequest(
+            task_id=uuid4(),
+            plan="plan",
+            approach="a" * 801,
+        )
+    assert "approach" in str(exc.value)
+
+
+def test_i_will_plan_request_rejects_overlong_subtask_title() -> None:
+    with pytest.raises(ValidationError):
+        IWillPlanRequest(
+            task_id=uuid4(),
+            plan="plan",
+            approach="a" * 150,
+            sub_tasks=[SubTaskCreate(title="t" * 201, description="d" * 30)],
+        )
+
+
+def test_i_will_plan_request_rejects_overlong_subtask_description() -> None:
+    with pytest.raises(ValidationError):
+        IWillPlanRequest(
+            task_id=uuid4(),
+            plan="plan",
+            approach="a" * 150,
+            sub_tasks=[SubTaskCreate(title="ok title", description="d" * 601)],
+        )
+
+
+def test_i_will_plan_request_rejects_thin_subtask_description() -> None:
+    """A sub_task description <20 chars fails the typed SubTaskCreate model."""
+    with pytest.raises(ValidationError):
+        IWillPlanRequest(
+            task_id=uuid4(),
+            plan="plan",
+            approach="a" * 150,
+            sub_tasks=[SubTaskCreate(title="ok title", description="too short")],
+        )
+
+
+def test_delegate_request_rejects_overlong_acceptance_criterion() -> None:
+    """An AC item >200 chars is rejected — a criterion that long is a restated
+    description, not a verifiable outcome."""
+    long_ac = "x" * 201
+    with pytest.raises(ValidationError) as exc:
+        DelegateRequest.model_validate(
+            {
+                "parent_task_id": uuid4(),
+                "title": "t",
+                "description": "add the new endpoint plus tests",
+                "assigned_to": "be-dev-1",
+                "team": "backend",
+                "task_type": "code",
+                "nature": "technical",
+                "estimated_complexity": "medium",
+                "acceptance_criteria": [long_ac],
+            }
+        )
+    assert "acceptance_criteria" in str(exc.value)
+
+
+def test_delegate_request_rejects_too_many_acceptance_criteria() -> None:
+    """An AC list >7 items is rejected — over-decomposition of criteria."""
+    with pytest.raises(ValidationError) as exc:
+        DelegateRequest.model_validate(
+            {
+                "parent_task_id": uuid4(),
+                "title": "t",
+                "description": "add the new endpoint plus tests",
+                "assigned_to": "be-dev-1",
+                "team": "backend",
+                "task_type": "code",
+                "nature": "technical",
+                "estimated_complexity": "medium",
+                "acceptance_criteria": [f"criterion {i}" for i in range(8)],
+            }
+        )
+    assert "acceptance_criteria" in str(exc.value)