In our testing, even the most generous representations give custom types a 10x edge (in size, allocations, and CPU time) over Envoy types.
In addition, they are more clear and strictly typed; using Envoy types would require us to put a lot of information in untyped `metadata` maps.

With this in mind, Ztunnel supports two xDS resources: `Address` and `Authorization`.

### Address Type

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                      Defines the mTLS mode used for peer authentication.

                      Valid Options: DISABLE, PERMISSIVE, STRICT
                    enum:
                    - UNSET
                    - DISABLE
                    - PERMISSIVE
                    - STRICT
                    type: string
                type: object
              portLevelMtls:

                      Defines the mTLS mode used for peer authentication.

                      Valid Options: DISABLE, PERMISSIVE, STRICT
                    enum:
                    - UNSET
                    - DISABLE
                    - PERMISSIVE
                    - STRICT
                    type: string
                type: object
              portLevelMtls:

  // for each duplicate field that is encountered. The request will
  // still succeed if there are no other errors, and will only persist
  // the last of any duplicate fields. This is the default in v1.23+
  // - Strict: This will fail the request with a BadRequest error if
  // any unknown fields would be dropped from the object, or if any
  // duplicate fields are present. The error returned from the server