badgr_badge 2.0.1

Refactor module for Drupal 10/11 compatibility, fix critical bugs, and enforce coding standards

- Update core_version_requirement from ^8 || ^9 to ^10 || ^11
- Replace deprecated functions: file_create_url(), file_save_data(),
file_copy(), entity_delete_multiple(), watchdog_exception()
- Fix fatal error: $this used in static methods in BadgrHelpers
- Fix undefined $logger variable in hook_uninstall
- Fix undefined $status_message and $access_token_data variables
- Fix BadgrConfigForm constructor to call parent properly
- Fix node->id() returning string with strict_types (int -> string|int)
- Fix AddToBackpack controller $currentUser conflict with ControllerBase
- Rename addtobackpack() method to add() to avoid PHP4 constructor detection
- Move node creation from validateForm() to submitForm() in BadgrConfigForm
- Convert BadgrHelpers from broken static class to proper DI service
- Rename all service methods from snake_case to lowerCamelCase
- Move global constants into BadgrService class constants
- Extract ensureAuthenticated() and apiRequest() to reduce duplication
- Add BadgrHelpers as a registered service with proper dependencies
- Add EntityTypeManager and LoggerFactory to BadgrService
- Change password field from textfield to password type
- Use getTriggeringElement() instead of comparing $op string
- Add separate submit handler for Import badges button
- Add config schema (config/schema/badgr_badge.schema.yml)
- Add default config (config/install/badgr_badge.badgrconfig.yml)
- Add declare(strict_types=1) to all PHP files
- Remove duplicate README.txt
- Remove commented-out routes referencing old udl_badgr module
- Update README.md with comprehensive documentation
- Fix all 310 phpcs errors and 55 warnings (Drupal + DrupalPractice)