Introduce ConstUint to make dependent types in DefaultConfig more adaptable

[conr2d]

Description

Resolves #6193

This PR introduces ConstUint as a replacement for existing constant getter types like ConstU8, ConstU16, etc., providing a more flexible and unified approach.

Integration

This update is backward compatible, so developers can choose to adopt ConstUint in new implementations or continue using the existing types as needed.

Review Notes

ConstUint is a convenient alternative to ConstU8, ConstU16, and similar types, particularly useful for configuring DefaultConfig in pallets. It enables configuring the underlying integer for a specific type without the need to update all dependent types, offering enhanced flexibility in type management.

Checklist

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