fix(chat): restore ~/.agents/skills/ as additional Codex skill dir

Codex CLI also reads skills from ~/.agents/skills/, so include it
alongside ~/.codex/skills/ in the skill storage spec. The Codex dir
stays first so it remains the preferred write target for new links,
while lookup and unlink scan both locations.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src-tauri/src/commands/experts.rs

@@ -851,7 +851,8 @@ pub async fn experts_unlink_from_agent(
 
     let _guard = mutation_lock().lock().await;
 
-    // Scan ALL global dirs for this agent to handle shared-dir agents.
+    // Scan ALL global dirs for this agent to handle shared-dir agents
+    // (Codex, Gemini and Cline all also point at `~/.agents/skills/`).
     // Remove the link wherever it is found.
     let dirs = scoped_skill_dirs(agent_type, AgentSkillScope::Global, None)
         .map_err(|_| ExpertsError::UnsupportedAgent(agent_type))?;