feat(occ): Cache command list to speed up occ

[come-nc]

Summary

This is a rough draft to track the idea and challenges.

TODO

• Only enable cache if instance is installed, maintenance is off and no upgrade required
• Cache in a PHP file for best performance
• Ideally add a PHP caching system we can re-use for autoloaders
• Reset cache on application install/removal/update
• Find out how to not break https://github.com/nextcloud/app_api/blob/main/appinfo/register_command.php

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI