feat(auth): Complete Auth Service implementation and fix Consul health checks

- Add VerifyPassword RPC to Identity Service
  - Added to proto file and generated code
  - Implemented in Identity Service gRPC server
  - Added to Identity Service client interface and gRPC client

- Complete RefreshToken implementation
  - Store refresh tokens in database using RefreshToken entity
  - Validate refresh tokens with expiration checking
  - Revoke refresh tokens on logout and token rotation

- Integrate Authz Service for role retrieval
  - Added AuthzServiceClient to Auth Service
  - Get user roles during login and token refresh
  - Gracefully handle Authz Service failures

- Require JWT secret in configuration
  - Removed default secret fallback
  - Service fails to start if JWT secret is not configured

- Fix Consul health checks for Docker
  - Services now register with Docker service names (e.g., audit-service)
  - Allows Consul (in Docker) to reach services via Docker DNS
  - Health checks use gRPC service names instead of localhost

This completes all TODOs in auth_service_fx.go and fixes the Consul
health check failures in Docker environments.

internal/ent/tx.go

@@ -16,6 +16,8 @@ type Tx struct {
 	AuditLog *AuditLogClient
 	// Permission is the client for interacting with the Permission builders.
 	Permission *PermissionClient
+	// RefreshToken is the client for interacting with the RefreshToken builders.
+	RefreshToken *RefreshTokenClient
 	// Role is the client for interacting with the Role builders.
 	Role *RoleClient
 	// RolePermission is the client for interacting with the RolePermission builders.
@@ -157,6 +159,7 @@ func (tx *Tx) Client() *Client {
 func (tx *Tx) init() {
 	tx.AuditLog = NewAuditLogClient(tx.config)
 	tx.Permission = NewPermissionClient(tx.config)
+	tx.RefreshToken = NewRefreshTokenClient(tx.config)
 	tx.Role = NewRoleClient(tx.config)
 	tx.RolePermission = NewRolePermissionClient(tx.config)
 	tx.User = NewUserClient(tx.config)