Align control plane config schema with proxy-core for wire compatibility (#35)

* Align control plane config schema with proxy-core for wire compatibility

The control plane's GatewayConfig and proxy-core's ProxyConfig had schema
drift after the dataplane migration. This adds the missing fields
(TlsConfig.inline_certificates, BackendRef.protocol/BackendProtocol) and
cross-deserialization roundtrip tests to ensure both directions work.

* Fix build against kopium-generated CRD bindings (standard channel)

The CI pipeline regenerates gateway-crds via kopium before building.
The standard-channel CRDs differ from stale local bindings:
- GatewayClassStatus has no supportedFeatures field (experimental only)
- HttpRouteStatusParents.conditions is Option<Vec<Condition>>
- HttpRouteRules has no name field (experimental only)

* Add test to dataplane crate so cargo nextest does not fail on zero tests

Author: RobbieMcKinstry

Cargo.lock

@@ -27,3 +27,6 @@ tokio.workspace = true
 tracing.workspace = true
 tracing-subscriber.workspace = true
 futures = "0.3"
+
+[dev-dependencies]
+proxy-core = { path = "../proxy-core" }