Support URIs with a 'mesh-' prefix

[dtobin]

What happened?

Service mesh URIs are used between conjure services in k8s with a special 'mesh-' prefix. Without special handling, requests for these URIs will fail with an unsupported URI scheme.

What did you want to happen?

Follow the behavior implemented by conjure clients for other languages (removing the prefix and disabling retries):

• dialogue: Support behaviour changes based on URIs with a 'mesh-' prefix dialogue#1048
• conjure-rust-runtime: Support the new mesh mode conjure-rust-runtime#81