feat: replace nginx placeholder with custom Pingora proxy; add Postfix MTA

Ingress:
- Deploy custom sunbeam-proxy (Pingora/Rust) replacing nginx placeholder
- HTTPS termination with mkcert (local) / rustls-acme (production)
- Host-prefix routing with path-based sub-routing for auth virtual host:
  /oauth2 + /.well-known + /userinfo → Hydra, /kratos → Kratos (prefix stripped), default → login-ui
- HTTP→HTTPS redirect, WebSocket passthrough, JSON audit logging, OTEL stub
- cert-manager HTTP-01 ACME challenge routing via Ingress watcher
- RBAC for Ingress watcher (pingora-watcher ClusterRole)
- local overlay: hostPorts 80/443, LiveKit TURN demoted to ClusterIP to avoid klipper conflict

Infrastructure:
- socket_vmnet shared network for host↔VM reachability (192.168.105.2)
- local-up.sh: cert-manager installation, eth1-based LIMA_IP detection, correct DOMAIN_SUFFIX sed substitution
- Postfix MTA in lasuite namespace: outbound relay via Scaleway TEM, accepts SMTP from cluster pods
- Kratos SMTP courier pointed at postfix.lasuite.svc.cluster.local:25
- Production overlay: cert-manager ClusterIssuer, ACME-enabled Pingora values

base/ory/kratos-values.yaml

@@ -39,7 +39,7 @@ kratos:
 
     courier:
       smtp:
-        connection_uri: "smtp://local:local@localhost:25/"
+        connection_uri: "smtp://postfix.lasuite.svc.cluster.local:25/?skip_ssl_verify=true"
         from_address: no-reply@DOMAIN_SUFFIX
         from_name: Sunbeam