Implement EZP-20321: Cluster support in FieldTypes

This PR implements cluster support for binary FieldTypes (Image, BinaryFile, Media) by means of a FieldType\FileService.

This FileService uses the internal IOService to interact with the IO layer, and is dedicated to operations from FieldType implementations.

Tasks:
- [x] Refactor the FileService
- [x] Create LegacyFileService
- [x] Adapt FieldType: BinaryBase
- [x] Adapt FieldType: Image
- [x] Adapt FieldType: BinaryFile
- [x] Adapt FieldType: Media
- [x] Refactor MetaData handling
- [x] Implement ImageSize metadata handler

Phase 2 tasks:
- [ ] Remove `IOService` from `API`, implementation goes to `Core`
- [ ] Remove references to `LegacyKernel` in `IOService`
- [ ] Make FieldType\FileService use IOService
- [ ] Remove the FileService interface
- [ ] Merge cluster implementation from `Core\FieldType\FileService\LegacyFileService` and `Core\IO\Legacy\LegacyHandler.php`
- [ ] Adapt metadata handling to work with FileService/IOService