fix(shared-manager): allow external claude symlink chains

tests/unit/shared-manager.test.ts

@@ -154,6 +154,71 @@ describe('SharedManager', () => {
     });
   });
 
+  describe('shared symlink lifecycle', () => {
+    it('preserves external ~/.claude symlinks during upgrade reconciliation', () => {
+      const manager = new SharedManager();
+      const externalCommandsDir = path.join(tempRoot, 'Documents', 'claude-config', 'commands');
+      const externalSettingsPath = path.join(
+        tempRoot,
+        'Documents',
+        'claude-config',
+        'settings.json'
+      );
+      const claudeCommandsPath = path.join(claudeDir(), 'commands');
+      const claudeSettingsPath = path.join(claudeDir(), 'settings.json');
+      const sharedCommandsPath = path.join(ccsDir(), 'shared', 'commands');
+      const sharedSettingsPath = path.join(ccsDir(), 'shared', 'settings.json');
+      const logSpy = spyOn(console, 'log').mockImplementation(() => {});
+
+      fs.mkdirSync(externalCommandsDir, { recursive: true });
+      fs.mkdirSync(path.dirname(externalSettingsPath), { recursive: true });
+      fs.mkdirSync(claudeDir(), { recursive: true });
+      fs.mkdirSync(path.join(ccsDir(), 'shared'), { recursive: true });
+      fs.writeFileSync(externalSettingsPath, JSON.stringify({ theme: 'dark' }), 'utf8');
+      fs.symlinkSync(externalCommandsDir, claudeCommandsPath, 'dir');
+      fs.symlinkSync(externalSettingsPath, claudeSettingsPath, 'file');
+      fs.symlinkSync(claudeCommandsPath, sharedCommandsPath, 'dir');
+      fs.symlinkSync(claudeSettingsPath, sharedSettingsPath, 'file');
+
+      manager.ensureSharedDirectories();
+
+      expect(
+        logSpy.mock.calls.some(([message]) =>
+          String(message).includes('Skipping commands: circular symlink detected') ||
+          String(message).includes('Skipping settings.json: circular symlink detected')
+        )
+      ).toBe(false);
+      expect(fs.lstatSync(sharedCommandsPath).isSymbolicLink()).toBe(true);
+      expect(
+        path.resolve(path.dirname(sharedCommandsPath), fs.readlinkSync(sharedCommandsPath))
+      ).toBe(claudeCommandsPath);
+      expect(fs.lstatSync(sharedSettingsPath).isSymbolicLink()).toBe(true);
+      expect(
+        path.resolve(path.dirname(sharedSettingsPath), fs.readlinkSync(sharedSettingsPath))
+      ).toBe(claudeSettingsPath);
+    });
+
+    it('still blocks real circular links back into ~/.ccs/shared', () => {
+      const manager = new SharedManager();
+      const claudeCommandsPath = path.join(claudeDir(), 'commands');
+      const sharedCommandsPath = path.join(ccsDir(), 'shared', 'commands');
+      const logSpy = spyOn(console, 'log').mockImplementation(() => {});
+
+      fs.mkdirSync(claudeDir(), { recursive: true });
+      fs.mkdirSync(sharedCommandsPath, { recursive: true });
+      fs.symlinkSync(sharedCommandsPath, claudeCommandsPath, 'dir');
+
+      manager.ensureSharedDirectories();
+
+      expect(
+        logSpy.mock.calls.some(([message]) =>
+          String(message).includes('Skipping commands: circular symlink detected')
+        )
+      ).toBe(true);
+      expect(fs.lstatSync(sharedCommandsPath).isDirectory()).toBe(true);
+    });
+  });
+
   describe('marketplace registry ownership', () => {
     it('writes global and instance registries with different authoritative install locations', () => {
       const globalRegistryPath = path.join(claudeDir(), 'plugins', 'known_marketplaces.json');