cli-tri cannot be required until its context is unique and unfiltered #3386

tri census pin --gate runs in cli-tri.yml. It is not one of the four required contexts, so a red census cannot block a merge — and a GitHub squash-merge never runs the local hook that would otherwise catch it. 3429f9c6 merged red for both reasons at once.

The obvious remedy is "make it required". Measured, that would break the repository, and for two independent reasons.

1. The context name is not unique

cli-tri.yml's job was displayed as build. So are the jobs in build-vivado-image.yml and coq-kernel.yml. GitHub matches a required check by context, so require: build names three workflows: it can be satisfied by the wrong one, or hang on one that did not run.

2. It was paths-filtered, so requiring it would hang most PRs

A required context that does not POST is not "passed" — it is pending forever. cli-tri.yml's pull_request trigger carried a paths: filter.

Measured over the last 40 merged PRs: 15 (38%) touched none of cli/**, .claude/skills/**, Cargo.toml, Cargo.lock, .github/workflows/** — every one of them would have hung.

What this PR does, and what it deliberately does not

Both prerequisites, priced before being made:

• unique context: the job is now displayed as cli-tri. Verified build is not among the four current required contexts, so nothing depends on the old name.
• no pull_request paths filter: it runs on every PR. Cost, measured rather than estimated: +38% of runs on a job whose median is 2.9 minutes, and which is green 58 of its last 60 runs (43 of 45 on pull_request). A gate that reddens rarely is one that can be required. The push: filter is kept — a master baseline only needs taking when the subject moves.

The ruleset is not touched. Adding cli-tri to the required set is a repository-settings change, which is the owner's alone; this makes it a single safe click instead of a change that would hang 38% of pull requests.

Boundary

• .github/workflows/build-vivado-image.yml
• .github/workflows/cli-tri.yml
• .github/workflows/coq-kernel.yml