Fix undefined $_SESSION warning when rebuilding menu cache

[Ibochkarev]

What changed and why

modMenu::rebuildCache() and other manager-language lookups passed bare $_SESSION into getOption(). Without an active session (CLI, early bootstrap, save/remove cache work) PHP 8+ logs Undefined global variable $_SESSION.

Changes:

• modX::getManagerLanguage() resolves language as $_SESSION ?? [] → config manager_language → cultureKey → en.
• modMenu::save / remove call clearCache() (clean on the menu partition) and skip session-keyed rebuild. Menu processors still call refresh(['menu' => []]) once, so OnCacheUpdate fires once.
• Rebuild/read paths use getManagerLanguage(): rebuildCache, manager header, lexicon, connector/manager request, country list, transport provider.
• getSubMenus drops identical dead lexicon branches.
• Login keeps Accept-Language. Session read uses $_SESSION ?? [].

How to test

1. Run php -l on the touched PHP files.
2. Run composer phpunit -- --filter 'modMenuTest|testGetManagerLanguage' (expect exit 0: 4 tests, 8 assertions).
3. Save or remove a manager menu item without an HTTP session. Confirm the log has no Undefined global variable $_SESSION from modMenu.php.
4. Set session manager_language, clear the menu cache, open the manager. Confirm the top menu renders in that language.

Related issue(s)/PR(s)

No GitHub issue. Production log:

PHPwarning: Undefined global variable $_SESSION at core/src/Revolution/modMenu.php:69.

Compatibility notes

Applies to PHP 8+ installs. No config changes. With an active manager session, language resolution matches the old getOption('manager_language', $_SESSION, …) chain.

Breaking change assessment

No public API removals. Adds modX::getManagerLanguage(). Menu mutate hooks clear the full menu partition instead of rewriting one language-keyed entry. Processors still fire OnCacheUpdate once. Safe for patch-level consumers.

Test coverage

• _build/test/Tests/Model/modXTest.php: getManagerLanguage without session and with session preference
• _build/test/Tests/Model/modMenuTest.php: rebuildCache without $_SESSION warning; clearCache removes menu partition keys
• Registered in _build/test/phpunit.xml

Contributors

AI tool use

Cursor (Composer) handled implementation and reviews: code-simplifier, code-reviewer, thermo-nuclear code-quality review, security-review.