Implement one-time-salt use and add comprehensive tests

[snoopdave]

This PR implements one-time use salts, improves URL matching for ignored URLs, and enhances security in ValidateSaltFilter and LoadSaltFilter. It also adds comprehensive unit tests for both filters to ensure proper functionality and edge case handling. The changes include:

• Implementing one-time use salts by removing them from the cache after validation
• Improving URL matching to consider full URLs including query parameters
• Enhancing security checks in ValidateSaltFilter
• Adding robust unit tests for both filters
• Refactoring code for better readability and maintainability

[mbien]

makes sense