## Summary
Chat-driven `fn_task_create` rejected freeform intake with `Approved
mission_lineage is required` even though the tool schema marks
`mission_lineage` as optional. That was FN-8307 mission admission
over-applied beyond autonomous heartbeat patrol.
This restores freeform chat/board-equivalent creates while keeping
idle-heartbeat mission-lineage enforcement.
## What changed
- **`fn_task_create` / `fn_delegate_task`**: omit `mission_lineage`
succeeds for user-directed surfaces; hard-require only when the tool is
registered with `requireMissionLineage` (idle heartbeat patrol).
- **Gates**: missing lineage is policy-governed (`allow` /
`require-approval` / `block`) instead of a hard pre-block, so
permanent-agent chat can create freeform tasks under normal policy.
- **Heartbeat no-task delegate**: also sets `requireMissionLineage:
true` so freeform off-mission work cannot bypass admission via
`fn_delegate_task`.
- Supplied lineage is still fully validated (Feature → Slice → Milestone
→ Mission) on every surface.
- Parent inheritance still applies when not in require mode.
## Test plan
- [x] Unit: freeform `fn_task_create` without lineage creates a task
with no `missionId`/`sliceId`
- [x] Unit: freeform `fn_delegate_task` without lineage succeeds
- [x] Unit: `requireMissionLineage: true` still hard-fails without
lineage
- [x] Unit: gates treat missing lineage as policy disposition, not hard
block
- [ ] CI gate green
## Symptom
**Original:** chat tool call `{ description: "Create a red button",
priority: "high" }` → `ERROR: Approved mission_lineage is required; no
task was created.`
**Expected after fix:** task is created freeform without mission fields.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit
- **Bug Fixes**
- Freeform chat task creation and delegation can now proceed without
`mission_lineage`.
- Permission policies continue to govern these actions, including
approval requirements.
- Autonomous idle patrols still require approved mission lineage before
creating or delegating tasks.
- Task creation no longer receives mission-specific metadata when no
lineage is provided.
- **Tests**
- Expanded coverage for freeform and mission-linked task creation,
delegation, and policy-gating scenarios.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->
f63047871c