Claiming `packages/engine/src/restart-recovery-coordinator.ts`.
## Census before/after
| File | Before | After |
|---|---:|---:|
| `packages/engine/src/restart-recovery-coordinator.ts` | 4 | **1** |
## These were deletions, not conversions
All three sites were fail-soft fallbacks behind an **optional**
`reviewColumns` parameter:
```ts
return (reviewColumns ? reviewColumns.has(task.column) : task.column === "in-review")
```
Production never took that branch — `self-healing.ts:13646-13649`
supplies the resolved set at every call site. So the correct change is
to make the parameter required and delete the literal, not to swap it
for a role lookup.
## The trap this hit, which would have shipped a crash
**Making the parameter required produced ZERO tsc errors.** That looked
like proof the fallback was unreachable. It is not: the engine
`tsconfig` covers `src` and not `__tests__`, so the type-checker cannot
see the callers that actually relied on the default. Running the tests
surfaced them immediately as `TypeError: Cannot read properties of
undefined (reading 'has')`.
This is the same class as finding 2 in
`docs/solutions/best-practices/proving-a-code-path-actually-runs.md` — a
negative result from a checker that cannot see the thing it is being
asked about. Anyone converting a `src`-only-typechecked package should
assume tsc is blind to test call sites.
The blast radius was also one site larger than grep suggested: the
`isRecoverableMissingWorktreeReviewFailure` **combiner** threads the set
to all three inner predicates. Its own comment already names why — *"a
caller cannot convert the outer question and leave one of the three
inner ones on the legacy id — the half-conversion shape this program
keeps finding."*
Tests now pass the set production always passes, preserving exactly what
each case asserted.
## Remaining 1, flagged not guessed
`L149` uses a different shape (`isReviewColumn ?? task.column ===
"in-review"`) whose callers I did not establish. Absence from grep is
not proof of no caller, so it stays counted.
## Verification
- census: 4 → 1
- `restart-recovery-coordinator` + `self-healing` — **424 tests green**
- `tsc --noEmit` clean; `pnpm lint` clean
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-authored-by: Claude Opus 5 (1M context) <noreply@anthropic.com>
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