A check runs as a cluster Job when checks.placement is job; the run records node and placement; process stays the default and unchanged #1692

Split from #1592.

Done looks like:

• [ ] Setting checks.placement: process | job with node selector and tolerations; default process.
• [ ] With job, a check goes through src/cluster/jobs.ts and its log streams into the run's log; the run records node and placement.
• [ ] Tests: a check reaches a verdict through the stand-in client; process placement is unchanged.

Start from today's main (0.7.107 or later). Before pushing run bun x tsc --noEmit, the test files this touches and test/check-list.test.ts; name every new test file in GATE in scripts/gate.ts in the same commit. Earlier tries went red because their branch was cut before main changed the home and asks tests: if the check is red on a test this pull does not touch, merge origin/main, run that test here, and push again; if it is still red, name it in the pull.

Parked by the crew: the preview's deploy failed and the decider saw no point in another try (pull #1714 closed). Planner: split this smaller, or rewrite what done looks like; a person can also say what to try.

Parked by the crew: the check stayed red through 2 automatic tries (pull #1733 closed).

Parked twice since a person last spoke here, so it is the planner's now. Every reason:

1. the preview's deploy failed and the decider saw no point in another try (pull #1714 closed)
2. the check stayed red through 2 automatic tries (pull #1733 closed)

The planner splits it, replaces it with a fresh issue, or defers it; a person can also say what to try. Nothing starts here until then, and the board lists it.

Deferred behind the Later gate (#595). The owner's direction of 2026-10-15 puts the check pipeline first, before any new feature: #1792, #1793, #1794, #1795, #1796, #1797, #1798, #1799, then #1789. Cluster Job placement for checks is a large change to the check runner itself; it should not race #1793–#1797, which reshape that same runner, and is rewritten against them once they land.

replaced by #1815. Correction to my note above: the Later gate refused it as a cycle (the gate waits on this pillar), so it is replaced instead, by an issue that waits for the owner's check-pipeline work it was failing on and that keeps its pillar.