Add pnpm pre-ci:affected for a fast, diff-scoped pre-push check

[dmerand]

About this stack

This stack came out of reviewing recent contributor and agent sessions in Shopify/cli, where the same avoidable friction kept recurring: failures found only after pushing, generated files regenerated by hand, local checks drifting from what CI actually enforces, and setup conventions relearned every time. The goal is to make the local dev loop mirror CI and keep the two single-sourced so they can't drift — then document it so people and agents stop rediscovering it.

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WHY are these changes introduced?

pnpm pre-ci mirrors CI's full --all targets, which makes it thorough but slow — slow enough that people won't reach for it on every change, which defeats the point of having an easy pre-push check. This adds a fast, diff-scoped version for the inner loop and keeps the full run for when you actually want that confidence.

WHAT is this pull request doing?

• Adds pnpm pre-ci:affected (and dev pre-ci:affected), the diff-scoped sibling of pre-ci.
• Each gate in bin/ci-gates.js now knows its affected form: type-check / lint / build use the nx :affected scripts, unit tests use vitest run --changed, and knip just runs (it's quick and has no affected mode).
• The codegen checks are skipped in affected mode unless your diff actually touches commands, flags, or GraphQL — and when they're skipped, the run reminds you to pnpm codegen if that applies. If it can't work out what changed, it errs toward running them.
• While here, the changed-file detection learned to handle quoted and renamed paths from git status, so the codegen heuristic doesn't quietly miss them.

pnpm pre-ci itself is unchanged. Dev tooling only, nothing user-facing.

How to test your changes?

1. On a code-only branch, pnpm pre-ci:affected runs the affected checks, runs knip, and skips codegen with a note.
2. On a branch that touches a command or a .graphql file, the codegen checks run.
3. pnpm check-ci-gates still passes — the gate set hasn't changed.

Post-release steps

None.

[dmerand]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• Document pre-submit workflow and local dev (AGENTS.md + docs/LOCAL_DEV.md) #7734
• Add pnpm pre-ci:affected for a fast, diff-scoped pre-push check #7751 👈 (View in Graphite)
• Add pnpm pre-ci mirroring PR CI gates, with manifest drift guard #7733
• Single-source codegen freshness checks via pnpm codegen scripts #7732
• main

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