test: shared hand-off + mutation infrastructure for feature PRs

[somethingwithproof]

Shared hand-off testing + mutation infrastructure consolidated from 8 in-flight feature PRs.

What this adds

• composer.json: infection/infection ^0.27 in require-dev and infection/extension-installer: true in config.allow-plugins (the plugin would otherwise be blocked by Composer 2.x).
• infection.json5 at repo root: baseline mutation config — Pest, MSI thresholds 70 / covered 80, 30s timeout, log under build/infection/. Per-feature filters live in the feature PRs.
• tests/HandOff/HandOffHelpers.php: shared helpers reused by every hand-off test:
  • cacti_handoff_stub_cacti_log() records cacti_log calls into a static buffer
  • cacti_handoff_get_log_buffer() / cacti_handoff_clear_log_buffer() for assertions and reset
  • cacti_handoff_temp_file(contents, extension) — auto-cleaned tempnam wrapper
  • cacti_handoff_make_zip(entries) — minimal valid ZIP builder for upload-validation tests
• tests/HandOff/<Feature>HandOffTest.php (8 files): boundary-crossing test suites consolidated from each feature PR. Each suite begins with a file_exists() / function_exists() guard against the feature's source file; on develop without the feature merged, the suite registers a single skipped test and returns. Once a feature PR merges, its suite activates automatically.
• phpunit.xml: registers a HandOff testsuite alongside Unit and Integration.
• docs/security/handoff-tests.md: explains the boundary-crossing assertion pattern and how to run mutation per feature.

Source PRs that contributed each suite

• CactiProcessHandOffTest.php — from feat(security): Symfony Process and Mime helpers #7073 (CactiProcess wrapper)
• CactiMimeHandOffTest.php — from feat(mime): add CactiMime helpers and validate package_import uploads #7074 (CactiMime wrapper)
• CliInvocationHandOffTest.php — from feat(cli): add Symfony Console plumbing and migrate two pilot scripts #7075 (Symfony Console plumbing)
• CactiSettingsHandOffTest.php — from feat(validator): add settings constraint validation pilot #7077 (Symfony Validator settings)
• ImportPackagePathHandOffTest.php — from fix(import): consolidate path hardening for import and package writes #6989 (import path-traversal hardening)
• OidStripHandOffTest.php — from fix: auto-detect and strip trailing .0 padding in SNMP OID indexes #7032 (OID stripping)
• CactiDispatchHandOffTest.php — from feat(security): add cacti_dispatch helper for action table authorisation #7063 (cacti_dispatch helper)
• HtmxLoaderHandOffTest.php — from feat(htmx): vendored htmx 2.0.6 loader + tests (tranche A of filter pilot) #7066 (htmx loader)

Each feature PR has been rebased to drop its local copy. Skip guards keep this PR green on develop today; the suites activate as feature PRs land.

What this does NOT change

• No CI gate on mutation. Mutation is operator-run locally before merging substantive changes; running it in CI on every PR would multiply the PHP matrix runtime by 5-10x with no caught-bug payoff at present coverage.
• 1.2.x branches are explicitly excluded — infection/infection transitively pulls Symfony components, and the project's policy is no Symfony on 1.2.x. Hand-off tests on 1.2.x branches still work via the same helpers but skip the mutation config.

Rollback

Two commits. Revert if there's pushback on the infection dev-dep.

[Copilot]

Pull request overview

Adds shared “hand-off” test infrastructure and baseline mutation-testing configuration so multiple feature PRs can rebase and drop duplicated scaffolding.

Changes:

• Add shared hand-off test helpers under tests/HandOff/ and track the directory in git.
• Register a HandOff testsuite in phpunit.xml and document the hand-off test pattern.
• Introduce a baseline infection.json5 and add infection/infection to require-dev (plus Composer allow-plugin entry).

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
tests/HandOff/HandOffHelpers.php	Adds shared helpers for log stubbing, temp files, and ZIP fixture creation used by HandOff tests.
tests/HandOff/.gitkeep	Ensures tests/HandOff/ is tracked before tests land.
phpunit.xml	Adds HandOff testsuite pointing to ./tests/HandOff.
infection.json5	Adds baseline Infection mutation-testing config and thresholds.
docs/security/handoff-tests.md	Documents the hand-off test pattern and how to run HandOff/mutation locally.
composer.json	Adds Infection dev dependency and allows Infection’s Composer plugin.

[Copilot]

cacti_handoff_stub_cacti_log() returns a by-ref static $buffer, but the shim actually records log lines into the separate static buffer inside cacti_handoff_log_buffer_ref(). As a result, callers using the return value from cacti_handoff_stub_cacti_log() will never see recorded entries. Make the stub return cacti_handoff_log_buffer_ref() by reference (and remove the extra static), or have cacti_handoff_record_log_line() append to the same static used by the stub.

[somethingwithproof]

Fixed — stub now returns cacti_handoff_log_buffer_ref() by reference.

[Copilot]

Defining cacti_log() via eval() is avoidable here and makes the helper harder to audit/debug. PHP supports conditional function declarations without eval (e.g., define function cacti_log(...) { ... } inside the if (!function_exists('cacti_log')) block). Also, the stub signature diverges from the real cacti_log() in lib/functions.php:1448 (types/defaults/return bool), which can cause surprising behavior when hand-off tests hit real call sites—consider matching the real signature and returning true.

Suggested change

	eval('function cacti_log($string, $output = false, $environ = "CMDPHP", $level = 0) { '
	. '\cacti_handoff_record_log_line($string, $environ, $level); '
	. '}');
	}
	return $buffer;
	}
	/*
	* Internal sink used by the eval'd cacti_log shim. Kept separate so
	function cacti_log(string $string, bool $output = false, string $environ = 'CMDPHP', int $level = 0): bool {
	cacti_handoff_record_log_line($string, $environ, $level);
	return true;
	}
	}
	return $buffer;
	}
	/*
	* Internal sink used by the cacti_log shim. Kept separate so

[somethingwithproof]

Fixed — eval removed; cacti_log is declared inline inside function_exists guard with the correct signature.

[Copilot]

ZipArchive::addFromString() can return false (e.g., invalid entry name). Right now failures are silently ignored, which can lead to tests operating on an incomplete ZIP. Check the return value and throw a RuntimeException when adding an entry fails.

Suggested change

	$zip->addFromString((string) $name, (string) $contents);
	if ($zip->addFromString((string) $name, (string) $contents) === false) {
	$zip->close();
	throw new RuntimeException('cacti_handoff_make_zip: failed to add ZIP entry "' . (string) $name . '"');
	}

[somethingwithproof]

Fixed — addFromString return value checked; failure closes the archive and throws RuntimeException.

[Copilot]

$schema points at vendor/infection/..., but this repo’s Composer vendor-dir is ./include/vendor (composer.json config). Updating the schema path to include/vendor/infection/infection/resources/schema.json keeps editor/IDE schema validation working with the project’s vendor layout.

Suggested change

	$schema: "vendor/infection/infection/resources/schema.json",
	$schema: "include/vendor/infection/infection/resources/schema.json",

[somethingwithproof]

Fixed.

[somethingwithproof]

Consolidated into #7124. The HandOff infrastructure, Integration suite, and infection config have been folded onto feat/test-infra-foundation along with the Pest test foundation. Closing here; please review on #7124.