deduplicate tests between stages, including CI

[twistedmelonman]

We may have a single test configured to run in multiple stages for valid and useful reasons. However, we should not needlessly mindlessly run the same tests on the same code in different stages. For example, the bats test run by the dotfiles repo takes five minutes and is run multiple times before pushing and on CI.
the task here is to build a logical path and sequence of tests, and skip those in later stages that were already performed and proven in earlier stages.
generally earlier stages are less expensive in time and money.

[twistedmelonman]

Resume note (parked 2026-09-30)

• What: stop running the same tests on the same code redundantly across stages (e.g. dotfiles' 5-minute bats suite runs both pre-push and in CI) — build a sequence where later, more expensive stages skip checks already proven in earlier, cheaper ones.
• Where it stopped: not started; no comments. Companion to per-repo test budget #140 (test budget) and CI checks: can we cache GHA environments? #142 (CI caching).
• First step: map which test suites actually run at each stage (pre-commit, pre-push, CI) per repo, to find the concrete duplication before designing the skip logic.

[twistedmelonman]

Closing. Each suite now runs once per change, in CI on the PR, as a required check:

• Pre-push no longer runs the full suites (ci(tests): run the suite once, in CI, as a required check claude-config#664, ci(tests): run the suite once, in CI, as a required check dotfiles#387). dotfiles keeps one 1s .git/config hygiene check.
• No push-to-main reruns: dropped in those two PRs and in ci(tests): drop the push-to-main rerun claude-wrapper#131. dev-env's new workflow (ci(tests): run the test suites on PRs #171) runs on PRs only.

Accepted gap: admin direct pushes to main are untested (enforce_admins=false).