operator: a site with a ClusterIP gateway never reaches Connected, and gateway.address does not help #457

Problem

When the operator creates this site's own GridSite and the gateway is a ClusterIP Service, the site never leaves Discovered. Connected and Available stay False with the message "gateway address not yet available", and setting gateway.address does not help.

Sites whose own GridSite is declared with a gateway endpoint are not affected.

Cause

• gateway.rs resolve returns the gateway.address override or a LoadBalancer address. classify treats every other Service type as no address.
• main.rs maybe_start_swim is the only caller of resolve, so the address only reaches SWIM's advertisement to peers. Without SWIM, as under Local membership, nothing reads gateway.address.
• local_records.rs creates the own GridSite with no gatewayEndpoint, and the phase step in controller/grid_site.rs reads only spec.gatewayEndpoint.

Fix

1. Resolve this site's gateway address independent of SWIM, from the override or LoadBalancer discovery, and pass it to the GridSite controller.
2. For the own GridSite, use spec.gatewayEndpoint when set, else the resolved address. The operator never writes the spec.
3. With neither set, report a steady reason such as GatewayAddressUndeclared, with a message telling the admin to set gateway.address.

Tests

• ClusterIP gateway with gateway.address set reaches Connected.
• ClusterIP gateway with neither set reads the new reason.
• Local membership without SWIM reads the override.