fix(lint): let make lint bootstrap golangci-lint on a fresh machine

[JonJagger]

make lint could not run at all on a machine that had never installed
golangci-lint: brew upgrade requires the formula to be present already, so
the target died with "Error: golangci-lint not installed" before the linter
ran. Checking for the formula and installing it when absent makes the target
idempotent.

The env var was also never reaching brew. Make expands $H (undefined) and
leaves the literal OMEBREW_NO_AUTO_UPDATE, so every make lint triggered a
full brew update, mutating the developer's brew installation as a side
effect of linting. Dropping the $ passes the assignment to the shell.

Presence-only, with no upgrade, also keeps local behaviour aligned with CI,
which uses golangci-lint-action rather than brew.

Closes#1038

[claude]

Claude finished @JonJagger's task in 1m 16s —— View job

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Review: PR #1041 — make lint bootstrap fix

• Read CLAUDE.md and gather context
• Inspect the Makefile diff vs origin/main
• Static checks (build/vet — n/a, Makefile-only change; no Go touched)
• Post review feedback

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Summary

The actual code change on the current HEAD is a single character: $HOMEBREW_NO_AUTO_UPDATE=1 → HOMEBREW_NO_AUTO_UPDATE=1. This is a real, worthwhile fix — in a Make recipe $H expands the undefined Make variable H to empty, leaving the literal OMEBREW_NO_AUTO_UPDATE=1 brew upgrade …, so the env var never reached brew and every make lint silently triggered a full Homebrew auto-update. Nicely diagnosed. ✅

⚠️ One thing to reconcile: PR metadata vs. code

The branch history tells a story worth flagging:

• 61335865 — switched to brew list … || brew install (the install-when-absent / fresh-machine bootstrap described in the PR body).
• c2f232b3 — reverted that, restoring brew upgrade and keeping only the $ fix.

As a result the current diff no longer matches the PR's title and body:

• Title: "let make lint bootstrap golangci-lint on a fresh machine"
• Body: "Checking for the formula and installing it when absent makes the target idempotent" + Closes #1038

But brew upgrade golangci-lint still fails with Error: golangci-lint not installed on a machine that never installed it — the exact #1038 scenario. So this branch as it stands does not close #1038.

Recommendation: either

1. re-add the self-bootstrapping form (see inline suggestion) so the title/body/Closes #1038 stay accurate, or
2. keep the scope as the pure $-expansion bugfix and update the title/body and drop Closes #1038 (point it at a bug describing the auto-update side effect instead).

Right now the title and closing keyword promise more than the code delivers, which will auto-close #1038 without actually fixing it.

On @gsavage's review questions

• "switched upgrade to install — mechanism for keeping it up-to-date?" — moot on current HEAD, since brew upgrade was kept; it does stay current.
• "should we pin to a specific version?" — currently unpinned, which matches CI's golangci-lint-actionversion: latest. Pinning would be a deliberate separate change if you want local to track a fixed version.

Nothing blocking from a correctness standpoint on the one-line fix itself — it's good. The main ask is to make the PR description and issue linkage match what the code now does.

[claude]

The $ expansion fix here is correct and worth keeping. In a Make recipe $H expands the (undefined) Make variable H to empty, leaving the literal OMEBREW_NO_AUTO_UPDATE=1 brew upgrade …. That stray token never sets the env var, so every make lint was actually triggering a full Homebrew auto-update. Dropping the $ passes the assignment through to the shell. Good catch. 👍

One caveat now that commit c2f232b3 reverted back to brew upgrade: on a machine that has never installed golangci-lint, brew upgrade golangci-lint still fails with Error: golangci-lint not installed — which is exactly the fresh-machine scenario in #1038. So with the current diff this target is not idempotent on a clean machine.

If keeping brew upgrade is the intended scope, consider making it self-bootstrapping without losing the upgrade behaviour:

Suggested change

	@HOMEBREW_NO_AUTO_UPDATE=1 brew upgrade golangci-lint
	@HOMEBREW_NO_AUTO_UPDATE=1 brew list golangci-lint >/dev/null 2>&1 \
	&& HOMEBREW_NO_AUTO_UPDATE=1 brew upgrade golangci-lint \
	|| HOMEBREW_NO_AUTO_UPDATE=1 brew install golangci-lint

Re: @gsavage's questions — with brew upgrade kept, the linter does stay current (mechanism for keeping it up-to-date), and it's unpinned, which matches CI's golangci-lint-action at version: latest. Pinning to a specific version would be a deliberate separate change if you want local == a fixed CI version.