feat(github): restructure labels for better categorization

Autolabeler changes:
- Separated scripts (ct/install/turnkey) from VMs (vm/)
- Added new labels: 'new vm', 'update vm', 'delete vm'
- Added 'documentation' label for docs/** changes
- 'github' label now includes README.md, SECURITY.md, LICENSE, CHANGELOG.md
- Removed misc/** from script labels (misc is for core functions)
- Added 'tools' label for tools/** directory
- Documentation checkbox now maps to 'documentation' (not 'maintenance')

Changelog changes:
- Added VM categories: New VMs, Updated VMs, Deleted VMs (with subcategories)
- Added Tools category with subcategories
- Added Documentation category (separate from Github)
- Github and API are now main categories (not under Maintenance)
- Removed Maintenance category (was redundant)

Label mapping summary:
- ct/install/turnkey → new script / update script / delete script
- vm/** → new vm / update vm / delete vm
- misc/*.func → core
- docs/** → documentation
- .github/**, README.md, etc. → github
- tools/** → tools (+ addon/pve-tool sub-labels)
- frontend/** → website
- frontend/public/json/** → json
- api/**, misc/api.func → api

Author: MickLesk