feat(config): add support for disabling OpenAI compatibility providers

- Introduced a `Disabled` flag to OpenAI compatibility configurations.
- Updated routing, auth selection, and API handling logic to respect the `Disabled` state.
- Extended relevant APIs, YAML configurations, and data structures to include the `Disabled` field.
- Adjusted all relevant loops and filters to skip disabled providers.

Closes: #3060 #3059 #2977

sdk/cliproxy/auth/conductor.go

@@ -1799,6 +1799,9 @@ func resolveOpenAICompatConfig(cfg *internalconfig.Config, providerKey, compatNa
 	}
 	for i := range cfg.OpenAICompatibility {
 		compat := &cfg.OpenAICompatibility[i]
+		if compat.Disabled {
+			continue
+		}
 		for _, candidate := range candidates {
 			if candidate != "" && strings.EqualFold(strings.TrimSpace(candidate), compat.Name) {
 				return compat

sdk/cliproxy/service.go

@@ -969,6 +969,9 @@ func (s *Service) registerModelsForAuth(a *coreauth.Auth) {
 			}
 			for i := range s.cfg.OpenAICompatibility {
 				compat := &s.cfg.OpenAICompatibility[i]
+				if compat.Disabled {
+					continue
+				}
 				if strings.EqualFold(compat.Name, compatName) {
 					isCompatAuth = true
 					// Convert compatibility models to registry models