Extract the Apple-Container gateway data plane out of `MacosInfraService` into
`MacosGateway`, the macOS implementation of the shared `Gateway` service.
`connect_to_orchestrator(url, gateway_token)` runs the triple-homed gateway
container (egress + agent + control networks) carrying the mitmproxy CA and the
pre-minted `gateway` token; `address()` / `ca_cert_pem()` /
`provisioning_transport()` round out the contract.
The infra service now composes the gateway: `ensure_running` mints the
role-scoped `gateway` JWT (it holds the signing key; the gateway never does —
#469) and hands it to `gateway().connect_to_orchestrator(...)`, and
`ca_cert_pem` delegates to the service. The inlined `_ensure_gateway_container`
+ CA-read are gone. `AppleGatewayTransport` + the gateway container name/label
now live with the gateway module, breaking the old infra→provision coupling.
Splits the gateway-run + CA tests out of test_macos_infra into a dedicated
test_macos_gateway; the infra tests mock `svc.gateway`.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
didericis
c4ccd74f9b