Support more built-in constraints

[CathalMullan]

See:

• https://learn.microsoft.com/en-us/aspnet/core/fundamentals/routing?view=aspnetcore-9.0#route-constraints
• https://docs.gofiber.io/guide/routing/#constraints

Let's go with:

• u8 -> u128
• usize
• i8 -> i128
• usize
• f32 + f64
• bool
• ipv4
• ipv6

Remember: these aren't validation. They only the general 'shape' of the segment is valid.

Only built-in types. Anything else can be easily implemented by the user/framework.