Big int

[ArnabChatterjee20k]

Summary by CodeRabbit

• New Features
  • Added support for a BIGINT attribute type for 64-bit signed/unsigned integer storage and consistent handling across adapters and queries.
• Bug Fixes
  • Improved type mapping and validation so bigint values are stored, cast, and queried reliably and size accounting is adjusted where applicable.
• Tests
  • Added unit and end-to-end tests covering BIGINT attribute creation, validation, document operations, increments/decrements, and boundary values.