Implementation for URI data type

[kgodey]

Problem

Users may want to store URIs in their database and utilize functionality that is specific to URIs such as validation and grouping. We should allow them to do so and implement this type appropriately in the backend.

Proposed solution

PostgreSQL does not have a built-in type to handle URIs, so we will create a custom type that users can install if they want to use it.

Tasks that need to completed:

• Design for URI data type #236
• Create URI custom type and handle it in the backend. #412
• Implement filtering options for the URI type #413
• Implement grouping options for the URI type #414
• Frontend implementation for URI Mathesar type #256

Moved to later milestone:

• Suggest popular/standard URI schemes as values for appropriate filter parameters #1097

Additional context

• The already implemented email custom type should serve as a good reference for implementing a custom URI type. We might also use/recommend https://github.com/petere/pguri instead of implementing our own.
• Mapping DB data types to Mathesar data types #269
• Mathesar should not depend on custom types being installed. #403

[kgodey]

Closing this since all subtasks are done.