Fix schema config field keys to use snake_case matching the factory

Co-authored-by: intel352 <77607+intel352@users.noreply.github.com>

Author: Copilot

schema/module_schema.go

@@ -957,9 +957,9 @@ func (r *ModuleSchemaRegistry) registerBuiltins() {
 		Inputs:      []ServiceIODef{{Name: "context", Type: "PipelineContext", Description: "Pipeline context with _http_request and _http_response_writer metadata"}},
 		Outputs:     []ServiceIODef{{Name: "result", Type: "StepResult", Description: "Proxy response status and target URL; Stop is always true"}},
 		ConfigFields: []ConfigFieldDef{
-			{Key: "backendUrlKey", Label: "Backend URL Key", Type: FieldTypeString, DefaultValue: "backend_url", Description: "Dot-path in pc.Current for the backend URL (e.g. backend_url or steps.resolve.url)"},
-			{Key: "resourceKey", Label: "Resource Key", Type: FieldTypeString, DefaultValue: "path_params.resource", Description: "Dot-path in pc.Current for the resource path suffix"},
-			{Key: "forwardHeaders", Label: "Forward Headers", Type: FieldTypeArray, ArrayItemType: "string", Description: "Header names to copy from the original request to the proxy request"},
+			{Key: "backend_url_key", Label: "Backend URL Key", Type: FieldTypeString, DefaultValue: "backend_url", Description: "Dot-path in pc.Current for the backend URL (e.g. backend_url or steps.resolve.url)"},
+			{Key: "resource_key", Label: "Resource Key", Type: FieldTypeString, DefaultValue: "path_params.resource", Description: "Dot-path in pc.Current for the resource path suffix"},
+			{Key: "forward_headers", Label: "Forward Headers", Type: FieldTypeArray, ArrayItemType: "string", Description: "Header names to copy from the original request to the proxy request"},
 			{Key: "timeout", Label: "Timeout", Type: FieldTypeString, DefaultValue: "30s", Description: "Proxy request timeout duration", Placeholder: "30s"},
 		},
 	})