feat(doctor): surface skill directory health in diagnostics

src/cli/doctor.ts

@@ -189,13 +189,31 @@ const checkSkills: Check = async (ctx) => {
     return { status: 'skip', label: 'Skills loaded', detail: '(config invalid)' };
   }
   try {
+    const skillDirs = {
+      bundled: ctx.config.skills.bundled_dir,
+      managed: ctx.config.skills.managed_dir,
+      workspace: ctx.config.skills.workspace_dir,
+    };
+    const missingDirs = Object.entries(skillDirs)
+      .filter(([, dir]) => Boolean(dir) && !existsSync(dir as string))
+      .map(([tier, dir]) => `${tier}:${dir as string}`);
+
     const { loadAllSkills } = await import('../skills/index.js');
     const skills = loadAllSkills({
-      bundledDir: ctx.config.skills.bundled_dir,
-      managedDir: ctx.config.skills.managed_dir,
-      workspaceDir: ctx.config.skills.workspace_dir,
+      bundledDir: skillDirs.bundled,
+      managedDir: skillDirs.managed,
+      workspaceDir: skillDirs.workspace,
     });
-    return { status: 'pass', label: 'Skills loaded', detail: `(${skills.length} skill(s))` };
+
+    const available = skills.filter((skill) => skill.available).length;
+    const unavailable = skills.length - available;
+    const detailParts = [`${skills.length} skill(s), ${available} available, ${unavailable} unavailable`];
+    if (missingDirs.length > 0) {
+      detailParts.push(`missing dirs: ${missingDirs.join(', ')}`);
+      return { status: 'warn', label: 'Skills loaded', detail: detailParts.join(' — ') };
+    }
+
+    return { status: 'pass', label: 'Skills loaded', detail: detailParts.join(' — ') };
   } catch (err) {
     return { status: 'fail', label: 'Skills loaded', detail: err instanceof Error ? err.message : String(err) };
   }