docs: the last narrow check commands say what they leave out

[JArmandoAnaya]

The check-command subset issue (#674) recorded two things: a kernel-scoped mypy and a browser-free frontend command were being read as the checks, and the decision (2026-08-18) to keep those narrow commands as an explicitly labelled inner loop with the subset relationship stated per row. Most of that decision is already on main. The one-home-per-rule consolidation (#705) gave AGENTS.md its inner-loop table with a does not cover column and named the two change categories that always escalate — state, gating or progress, and the shape of a published wire model — and the targeted-checks follow-up (#706) reconciled CONTRIBUTING.md and the skills to the same statement. This pull request finishes the issue by fixing the three places that still named a narrow command as the check with nothing beside it.

What changed

README.md called uv run mypy src/visionset/kernel and pnpm test "common checks" and pointed at CONTRIBUTING.md only for the wheel build and the thirty-minute flow. The line now calls them the inner loop, says beside each what it leaves out — the kernel only, no browser — and states that every command there is a subset of what CI runs on each pull request, linking to the section that lists what each one does not cover.

docs/content/architecture/backend/kernel.md presented the kernel-only mypy as the mypy run. The strict flags are per-module configuration in pyproject.toml, so uv run mypy src/visionset — what CI runs — applies them to the kernel and the ordinary ones everywhere else; the page now says so and names the kernel-only command as the iterating subset that sees nothing outside the kernel.

docs/content/architecture/frontend/README.md listed the three workspace commands and said check.sh "runs all three, plus the two browser suites", which leaves the reader to infer that the three run no browser. It now says that directly — anything only chromium can see passes them — and that CI runs all five on every pull request.

One clause of the decision is superseded, and this records it

The decision comment on the issue says a full local pass happens once, immediately before a pull request is opened. The targeted-checks change (#706) moved the policy past that: bash scripts/check.sh is the comprehensive local run for the moments a developer deliberately chooses its cost, and is no longer a routine step before a commit, push, or pull request. The reading-CI obligation and the two escalation categories from the decision stand unchanged in AGENTS.md. Nothing here reopens that; the issue is closed against the policy as main now states it.

Test plan

Targeted, per the policy. The docs site link check runs in CI as docs site.

node --test tests/scripts/docs_links.test.mjs     7 pass, 0 fail
git diff --check                                  clean

Found, not fixed

Nothing.

Closes #674