fix(web): fail check-docs on stale install snippets (#3770)

[Hmbown]

Summary

Closes #3770. web/scripts/check-docs.mjs printed FAIL for stale install snippets but then fell through to [check-docs] PASS without exiting non-zero, so CI could miss public install-copy drift.

Change

The stale-snippet branch now calls process.exit(1) (mirroring checks 1 & 2), and the final PASS is only printed when every check passes.

Validation

• cd web && node scripts/check-docs.mjs on a fresh tree → [check-docs] PASS, exit 0.
• Stale snippets now take the exit(1) path before any PASS line.

Acceptance criteria

• Exits status 1 when checkInstallSnippets() returns stale entries
• Final PASS printed only if every check passed
• Clean npm run check:docs still passes

[claude]

Claude finished @Hmbown's task in 1m 6s —— View job

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Code Review

• Gather context and read changed files
• Analyze the diff for correctness and edge cases
• Post review findings

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The fix is correct and focused. Here's the full analysis:

Logic before and after

Before:

if (!install.ok && !install.note) {
  // prints FAIL + stale details…
} else {
  console.log(`[check-docs] OK — install snippets…`);
}
console.log("[check-docs] PASS");  // ← always reached, even on failure

After:

if (!install.ok && !install.note) {
  // prints FAIL + stale details…
  process.exit(1);  // ← gate now actually closes
}
console.log(`[check-docs] OK — install snippets…`);  // only reached on success
console.log("[check-docs] PASS");

The early-exit transformation is equivalent to the original else branch but now prevents fall-through. ✅

Edge cases — all handled correctly

ok	note	Condition !ok && !note	Behaviour
false	"could not derive version"	false	Soft-pass (inconclusive) — logs note, no exit ✅
true	"install page not found"	false	Soft-pass — logs note, exits 0 ✅
false	undefined	true	Hard-fail — logs stale entries, exits 1 ✅
true	undefined	false	Clean pass ✅

The distinction between "inconclusive" (ok: false + note) and "definitively stale" (ok: false, no note) is preserved.

Minor nit — comment references issue number

web/scripts/check-docs.mjs:146-148 — The two-line comment (// #3770: a stale install snippet…) references the issue number. Per repo guidelines, task/fix context belongs in the PR description rather than inline, since it rots as the codebase evolves. The comment could either be dropped entirely (the exit(1) mirrors checks 1 & 2 above and is self-evident) or trimmed to a one-liner without the issue reference. This is a minor style nit, not a blocker.

Verdict

LGTM. The bug fix is minimal, correct, and consistent with how checks 1 and 2 are structured. The one nit above is optional cleanup.