feat(api): add route validation endpoint with WebSocket support

Adds a new `/route/validate` endpoint that accepts YAML-encoded route
configurations for validation. Supports both synchronous HTTP requests
and real-time streaming via WebSocket for interactive validation workflows.

Changes:
- Implement Validate handler with YAML binding in route/validate.go
- Add WebSocket manager for streaming validation results
- Register GET/POST routes in handler.go
- Regenerate Swagger documentation

internal/api/v1/file/validate.go

@@ -20,7 +20,7 @@ type ValidateFileRequest struct {
 // @Summary		Validate file
 // @Description	Validate file
 // @Tags			file
-// @Accept		json
+// @Accept		application/yaml
 // @Produce		json
 // @Param			type	query		FileType	true	"Type"
 // @Param			file	body		string		true	"File content"