* 🔧 refactor: Centralize Collection Existence Checks for Permissions Migration
* Replace individual collection existence checks with a unified function `ensureRequiredCollectionsExist` in the database utility module.
* Update migration scripts for agents and prompts to utilize the new function, ensuring all required collections are verified for existence in a single call.
* Remove redundant collection existence logic from migration files, improving code maintainability and clarity.
* chore: import order in migration scripts
* 🔧 test: Update Token Test Cases for Realistic Scenarios
* Changed email in test data to 'user1-alt@example.com' for a more realistic scenario.
* Clarified expectation comment for token retrieval to indicate it finds the only matching token based on criteria.
* Refactor deleteTokens to use an array of conditions for querying, ensuring only specified fields are considered for deletion.
* Add error handling to prevent accidental deletion when no query parameters are provided.
* Update AuthService to match the new deleteTokens signature by passing an object instead of a string for email.
