refactor(access): migrate to SDKConfig for authentication and provider management

- Replaced `config.Config` with `SDKConfig` in authentication and provider logic for consistency with SDK changes.
- Updated provider registration, reconciliation, and build functions to align with the `SDKConfig` structure.
- Refactored related imports and handlers to support the new configuration approach.
- Improved clarity and reduced redundancy in API key synchronization and provider initialization.

sdk/config/config.go

@@ -11,4 +11,79 @@ type SDKConfig struct {
 
 	// RequestLog enables or disables detailed request logging functionality.
 	RequestLog bool `yaml:"request-log" json:"request-log"`
+
+	// APIKeys is a list of keys for authenticating clients to this proxy server.
+	APIKeys []string `yaml:"api-keys" json:"api-keys"`
+
+	// Access holds request authentication provider configuration.
+	Access AccessConfig `yaml:"auth" json:"auth"`
+}
+
+// AccessConfig groups request authentication providers.
+type AccessConfig struct {
+	// Providers lists configured authentication providers.
+	Providers []AccessProvider `yaml:"providers" json:"providers"`
+}
+
+// AccessProvider describes a request authentication provider entry.
+type AccessProvider struct {
+	// Name is the instance identifier for the provider.
+	Name string `yaml:"name" json:"name"`
+
+	// Type selects the provider implementation registered via the SDK.
+	Type string `yaml:"type" json:"type"`
+
+	// SDK optionally names a third-party SDK module providing this provider.
+	SDK string `yaml:"sdk,omitempty" json:"sdk,omitempty"`
+
+	// APIKeys lists inline keys for providers that require them.
+	APIKeys []string `yaml:"api-keys,omitempty" json:"api-keys,omitempty"`
+
+	// Config passes provider-specific options to the implementation.
+	Config map[string]any `yaml:"config,omitempty" json:"config,omitempty"`
+}
+
+const (
+	// AccessProviderTypeConfigAPIKey is the built-in provider validating inline API keys.
+	AccessProviderTypeConfigAPIKey = "config-api-key"
+
+	// DefaultAccessProviderName is applied when no provider name is supplied.
+	DefaultAccessProviderName = "config-inline"
+)
+
+// SyncInlineAPIKeys updates the inline API key provider and top-level APIKeys field.
+func SyncInlineAPIKeys(cfg *SDKConfig, keys []string) {
+	if cfg == nil {
+		return
+	}
+	cloned := append([]string(nil), keys...)
+	cfg.APIKeys = cloned
+	if provider := cfg.ConfigAPIKeyProvider(); provider != nil {
+		if provider.Name == "" {
+			provider.Name = DefaultAccessProviderName
+		}
+		provider.APIKeys = cloned
+		return
+	}
+	cfg.Access.Providers = append(cfg.Access.Providers, AccessProvider{
+		Name:    DefaultAccessProviderName,
+		Type:    AccessProviderTypeConfigAPIKey,
+		APIKeys: cloned,
+	})
+}
+
+// ConfigAPIKeyProvider returns the first inline API key provider if present.
+func (c *SDKConfig) ConfigAPIKeyProvider() *AccessProvider {
+	if c == nil {
+		return nil
+	}
+	for i := range c.Access.Providers {
+		if c.Access.Providers[i].Type == AccessProviderTypeConfigAPIKey {
+			if c.Access.Providers[i].Name == "" {
+				c.Access.Providers[i].Name = DefaultAccessProviderName
+			}
+			return &c.Access.Providers[i]
+		}
+	}
+	return nil
 }