fix(NO-TASK): Repair SlowMetaQuery sniff under WPCS 3

[aaronware]

Problem

SlowMetaQuerySniff calls three helpers that WordPressCS\WordPress\Sniff provided in WPCS 2 and that WPCS 3 removed in favour of PHPCSUtils. composer.json requires wp-coding-standards/wpcs: ^3.3.0, so all three are undefined at runtime and the sniff raises a fatal error the moment it sees a meta_query instead of reporting anything:

PHP Fatal error:  Uncaught Error: Call to undefined method
Linchpin\Sniffs\Performance\SlowMetaQuerySniff::find_array_open_close()
  at Linchpin/Sniffs/Performance/SlowMetaQuerySniff.php:129

Net effect: the sniff currently provides zero protection, and any consuming project that adds a meta_query gets a hard PHPCS crash rather than a warning.

Fix

Port the three removed calls to their PHPCSUtils equivalents (PHPCSUtils already ships as a WPCS 3 dependency):

WPCS 2 (removed)	Replacement
find_array_open_close()	Arrays::getOpenClose() — same opener/closer shape; its false return is now handled
strip_quotes()	TextStrings::stripQuotes()
addMessage()	MessageHelper::addMessage()

The last two are kept as thin protected shims so the sniff's existing call sites and message codes are untouched, keeping the diff small.

Also makes $stackPtr explicitly nullable in check_compare_value(). Implicit nullable parameters are deprecated as of PHP 8.4, and the notice fires on every phpcs run:

Deprecated: Linchpin\Sniffs\Performance\SlowMetaQuerySniff::check_compare_value():
Implicitly marking parameter $stackPtr as nullable is deprecated ... on line 283

Beyond the noise, that notice is written to stdout ahead of the report, which corrupts machine-readable formats — it breaks --report=json parsing.

Verification

⚠️ Verified with a real PHPCS run, not the test suite. tests/ cannot currently load WordPressCS\WordPress\AbstractArrayAssignmentRestrictionsSniff, so composer test errors with 2 errors / 0 assertions identically before and after this change. That broken harness is pre-existing and out of scope here, but it is how the WPCS 3 breakage went unnoticed — tests/fixtures/fail/meta-queries.php exists but never actually exercises the sniff. Worth a follow-up.

Running the sniff through a project with a working WPCS install:

Before — fatal, run aborted.

After — compare => 'LIKE':

 14 | WARNING | meta_query is using LIKE comparison, which is non-performant.
    |         | (Linchpin.Performance.SlowMetaQuery.nonperformant_comparison)

Nested relation clauses recurse and report per-clause as intended, and the deprecation notice is gone.

Note for reviewers

This restores a sniff that has been dead, so consuming projects may see new warnings on merge. The sniff warns on any comparison other than EXISTS/NOT EXISTS — including = — which is its existing design, not a change made here. Worth a heads-up in the release notes.

🤖 Generated with Claude Code