fix(cli): keep dag validate success output on stdout

Author: OnlyYu1996

src/cortex-cli/src/agent_cmd/tests.rs

@@ -3,10 +3,9 @@
 #[cfg(test)]
 mod tests {
     use crate::agent_cmd::cli::{CopyArgs, ExportArgs};
-    use crate::agent_cmd::loader::{
-        load_builtin_agents, parse_frontmatter, read_file_with_encoding,
-    };
+    use crate::agent_cmd::loader::{load_builtin_agents, parse_frontmatter};
     use crate::agent_cmd::types::AgentMode;
+    use crate::utils::file::read_file_with_encoding;
 
     #[test]
     fn test_read_file_with_utf8() {

src/cortex-cli/src/dag_cmd/commands.rs

@@ -5,7 +5,7 @@ use cortex_agents::task::{DagHydrator, DagStore, TaskStatus};
 use std::collections::HashMap;
 use std::io::{self, Write};
 
-use crate::styled_output::{print_error, print_info, print_success};
+use crate::styled_output::{print_error, print_info, print_success, println_success};
 
 use super::args::{
     DagCreateArgs, DagDeleteArgs, DagGraphArgs, DagListArgs, DagResumeArgs, DagRunArgs,
@@ -361,7 +361,7 @@ pub async fn run_validate(args: DagValidateArgs) -> Result<()> {
             // Verify topological sort works
             match dag.topological_sort() {
                 Ok(order) => {
-                    print_success(&format!(
+                    println_success(&format!(
                         "✓ DAG is valid ({} tasks, no cycles detected)",
                         dag.len()
                     ));