VSN-1859/ feat(establishment-manager): implement complete profile update and S3 utils integration
- Added POST /update-complete-establishment-profile endpoint for full establishment updates (including logo upload to S3)
- Implemented updateCompleteEstablishmentProfile() handling DTO mapping, S3 uploads, and manager synchronization
- Created new S3Utils class to generate unique file names and assist with S3 file handling
- Added DELETE /delete-manager endpoint to safely remove establishment managers
- Added GET /check-email and /check-phone endpoints to validate manager email and phone uniqueness
- Implemented existsManagerByEmail() and existsManagerByPhone() methods in service layer
- Added PUT /set-as-primary-manager endpoint to promote a manager to PRIMARY type
- Implemented deleteEstablishmentManager() and setManagerAsPrimary() logic
- Improved exception handling for FunctionalException, TechnicalException, and S3FunctionalException
Closes VSN-1859