Implement Smithy RPC v2 CBOR protocol

[david-perez]

Smithy RPC v2 CBOR protocol is a new protocol that has been added to Smithy 1.47 (release notes). This issue tracks all subtasks needed to add support for the protocol in smithy-rs.

• [x] https://github.com/smithy-lang/smithy-rs/pull/3552
• [x] https://github.com/smithy-lang/smithy-rs/issues/3709
• [x] Implement server-side support (https://github.com/smithy-lang/smithy-rs/pull/2544)
• [ ] #3772
• [ ] We need more and better tests to be confident in our implementation! https://github.com/smithy-lang/smithy/issues/2325

Paper cuts:

• [ ] https://github.com/smithy-lang/smithy-rs/issues/3745