Refactor Custom GraphQL Scalars to Basic Types

## Problem

We currently have several custom GraphQL scalars in our codebase that have been identified as potentially confusing and adding unnecessary complexity. These custom scalars should be converted to basic GraphQL scalar types to improve code clarity and maintainability.

## Proposal

- Identify all custom scalars in the codebase
- Evaluate each custom scalar and map it to an appropriate basic GraphQL scalar
- Update schema definitions to use basic scalars
- Update resolvers and input validation logic accordingly
- Update client-side code to handle the new scalar types
## Questions

- Do we need to maintain any custom scalars for specific use cases?

JIRA Issue: BA-43