Hand a limb to the planner to re-plan as fewer, larger pieces #761

Pillar: P0 Trust (umbrella #586), with the alignment set. Split out of #733; waits for it. Built like the hand-over in #613.

The owner, 2026-10-05: "There is a lot ... it's harder to make impactful decisions. I want to trim at a limb, not each leaf." One of the limb actions he asked for is to hand a limb to the planner to re-plan as fewer, larger pieces.

Outcome (what a person sees). On a milestone with too many small leaves he presses one action. The planner's next pass is given that limb, and comes back with fewer, larger issues in place of the old ones. Nothing he asked for is lost: each old issue is closed as split into what replaces it.

Today. The planner is asked when the map is thin or when the crew hands it a twice-parked issue (#613). A person cannot hand it a limb.

Acceptance.

• [ ] "Re-plan" on the milestone page hands the limb to the planner: its next pass is owed, once, even with a full map and even after it declined the direction, and its task names the limb and lists every open issue beneath it.
• [ ] The planner may close an open issue beneath a handed-over limb only as split into open issues made since the hand-over, the same rule as #613. It may not drop a person's issue.
• [ ] Until the planner has answered, the limb says "with the planner" on the milestone page and nothing beneath it is picked by the crew.
• [ ] A preview before the hand-over lists every issue the planner will be given; afterwards the milestone shows what changed (which issues were closed into which).
• [ ] A person may take it back before the planner runs.
• [ ] Refusing tests first: a reader, a crew agent and an ro token cannot hand a limb over; the planner cannot close anything outside the limb through this.

Contract (the owner's rule, docs/VISION.md).

• [ ] One interface per job. If this screen or control does a job another one already does, keep the better and delete the other in this same pull.
• [ ] Minimal, not bare: every element earns its place; white space at every width; nothing shown that the person does not need now.
• [ ] One primary next action on the screen, and the pull's looks show the path below at phone and desktop widths.
• [ ] The pull says what it removes for every screen or control it adds.

The path: the owner on a limb with many leaves presses Re-plan; he reads what the planner will be given; he confirms; later the milestone shows fewer, larger pieces.

Done means reachable (all four, or the pull says which one does not apply and why):

• Page: Re-plan on /:owner/:name/milestones/:number, and "with the planner" while it waits
• MCP: limb with replan, dry-run by default
• Test: the hand-over is owed once; the brief lists the limb; the planner's grant and its refusals; take it back
• Look: the preview and the milestone after, phone and desktop, on the pull

Start from: src/crew/parks.ts and src/crew/autonomy.ts (planIfThin, the #613 hand-over), src/crew/brief.ts (parkedTwiceLines), src/actions/issues.ts (handedToPlanner), src/core/milestones.ts.

Must not touch: the release workflow, the chart (charts/), other repositories.

replaced by #2585. Pull #2561 stopped after three change requests, and a comment on it does not start a builder. #2585 starts from that pull's branch and does only what the reviews asked.

Closed: already done on main in c830d368 (pull #2561).