test(restart-chaos): reach the stop-and-retain crash point with --daytona-reuse-lease (#20049)

## Thinking Path

> - Paperclip is the open source app people use to manage AI agents for
work
> - The restart-chaos crash-point suite kills the server at named
points, then checks that recovery restores every invariant
> - On Daytona, `environment.stop_retain.after_claim_before_stop` was
never reached, because no workload produced a stop-and-retain release
> - A per-turn run on a reusable sandbox lease ends every turn with
`stop_and_reuse`, which releases through exactly that stop-only claim
> - This pull request adds `--daytona-reuse-lease`, so the chaos Daytona
environment keeps reusable sandboxes and the point is reachable
> - The benefit is live coverage of the stop-and-retain crash window

## Linked Issues or Issue Description

This is a follow-up from the Phase 2 durable-ownership data
(`doc/plans/2026-11-07-phase2-reconciler-data.md`, "Not covered").
Related: #19937 (crash-point suite) and #20042 (stop-only claim fence
renewal). No duplicate PR was found.

**What happened?**

The Daytona crash-point run `cp-20261108T104102` reported
`environment.stop_retain.after_claim_before_stop` as `not_reached`. The
point needs a stop-and-retain intent, and the chaos Daytona environment
is created with ephemeral leases.

**Expected behavior**

A flag lets a Daytona wave or crash-point run use reusable leases. A
per-turn run then stops and keeps its sandbox, and the point is reached
and graded.

**Steps to reproduce**

1. Run `node scripts/crash-points.mjs --env daytona --daytona-image
<image> --points environment.stop_retain.after_claim_before_stop
--adapters codex --workloads A1`.
2. Before this PR the point is `not_reached`.
3. With `--daytona-reuse-lease --lifecycle per_turn` it is reached.

**Paperclip version or commit**

`master` at `8475826d2d` (the signed image `c24059f1…` revision).

## What Changed

- `--daytona-reuse-lease` (wave and crash-point suite, Daytona only)
creates the chaos environment with `reuseLease: true`. The crash-point
suite passes the flag through.
- The R6 sandbox sweep counts a **stopped** sandbox behind a **released
`reuse_by_environment`** lease as kept for reuse, not a leak. A later
run on the same workspace resumes it, because reuse accepts released and
retained leases. A running sandbox, or a stopped one behind an ephemeral
lease, is still a leak.
- The crash-point registry prerequisite and the README name the flag.

## Verification

- Live, Daytona, codex A1, from the image revision `8475826d2d`:
- `cp-20261108T132149`: the point was **reached** and settled with no
invariant violations. R6 flagged the stopped reusable sandbox as a leak,
which led to the sweep fix.
- `cp-20261108T133351`, with the sweep fix: **pass**. 0 orphaned
sandboxes, 0 held leases, the environment deleted, and nothing left
running.
- `pnpm exec vitest run --config tests/restart-chaos/vitest.config.ts`
passes `daytona-sweep`, `scheduler` and `crash-points` (52/52). `tsc -p
tests/restart-chaos/tsconfig.json` is clean.

## Risks

- Test harness only; the registry change is prerequisite text. Without
the flag, waves behave as before.

## Model Used

- Anthropic Claude Opus 5.5 (`claude-opus-5-5`), via Claude Code with
tool use.

## Checklist

- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub `#NNN` / `github.com/paperclipai/paperclip`
URLs)
- [x] My branch name describes the change (e.g. `docs/...`, `fix/...`)
and contains no internal Paperclip ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [x] I have updated relevant documentation to reflect my changes
- [x] I have considered and documented any risks above
- [ ] All Paperclip CI gates are green
- [ ] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
- [x] I will address all Greptile and reviewer comments before
requesting merge

🤖 Generated with [Claude Code](https://claude.com/claude-code)

---------

Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>

packages/shared/src/crash-point-registry.ts

@@ -113,7 +113,7 @@ export const CRASH_POINTS = {
     environments: ["daytona"],
     kinds: ["environment_stop_and_retain_intent"],
     invariants: ["I2", "I7"],
-    prerequisite: "A stop-and-retain intent: a run whose sandbox must be stopped but kept, for a native workspace export resume.",
+    prerequisite: "A stop-and-retain intent: run with --daytona-reuse-lease, so each per-turn run stops and keeps its reusable sandbox.",
   },
   "environment.lease.after_release_before_runtime_services": {
     description: "The run's environment leases are released; its workspace runtime services are not.",