Add UI for skill enable/disable. (#9627)

"/skill" will now allow you to enable/disable skills:
<img width="658" height="199" alt="image"
src="https://github.com/user-attachments/assets/bf8994c8-d6c1-462f-8bbb-f1ee9241caa4"
/>

codex-rs/core/src/codex.rs

@@ -1,4 +1,5 @@
 use std::collections::HashMap;
+use std::collections::HashSet;
 use std::fmt::Debug;
 use std::path::PathBuf;
 use std::sync::Arc;
@@ -2481,8 +2482,7 @@ mod handlers {
         for cwd in cwds {
             let outcome = skills_manager.skills_for_cwd(&cwd, force_reload).await;
             let errors = super::errors_to_info(&outcome.errors);
-            let enabled_skills = outcome.enabled_skills();
-            let skills_metadata = super::skills_to_info(&enabled_skills);
+            let skills_metadata = super::skills_to_info(&outcome.skills, &outcome.disabled_paths);
             skills.push(SkillsListEntry {
                 cwd,
                 skills: skills_metadata,
@@ -2735,7 +2735,10 @@ async fn spawn_review_thread(
         .await;
 }
 
-fn skills_to_info(skills: &[SkillMetadata]) -> Vec<ProtocolSkillMetadata> {
+fn skills_to_info(
+    skills: &[SkillMetadata],
+    disabled_paths: &HashSet<PathBuf>,
+) -> Vec<ProtocolSkillMetadata> {
     skills
         .iter()
         .map(|skill| ProtocolSkillMetadata {
@@ -2755,6 +2758,7 @@ fn skills_to_info(skills: &[SkillMetadata]) -> Vec<ProtocolSkillMetadata> {
                 }),
             path: skill.path.clone(),
             scope: skill.scope,
+            enabled: !disabled_paths.contains(&skill.path),
         })
         .collect()
 }