feat(skills): migrate Gemini CLI to config-driven native skills

Replace TOML-based .gemini/commands output with native SKILL.md output
in .gemini/skills/. Gemini CLI confirms native skills support per
geminicli.com/docs/cli/skills/.

- Update platform-codes.yaml: target_dir, skill_format, legacy_targets
- Add test Suite 23: 9 assertions (config, install, legacy, reinstall)
- Add Gemini CLI section to migration checklist

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

test/test-installation-components.js

@@ -1215,6 +1215,65 @@ async function runTests() {
 
   console.log('');
 
+  // ============================================================
+  // Suite 23: Gemini CLI Native Skills
+  // ============================================================
+  console.log(`${colors.yellow}Test Suite 23: Gemini CLI Native Skills${colors.reset}\n`);
+
+  try {
+    clearCache();
+    const platformCodes23 = await loadPlatformCodes();
+    const geminiInstaller = platformCodes23.platforms.gemini?.installer;
+
+    assert(geminiInstaller?.target_dir === '.gemini/skills', 'Gemini target_dir uses native skills path');
+
+    assert(geminiInstaller?.skill_format === true, 'Gemini installer enables native skill output');
+
+    assert(
+      Array.isArray(geminiInstaller?.legacy_targets) && geminiInstaller.legacy_targets.includes('.gemini/commands'),
+      'Gemini installer cleans legacy commands output',
+    );
+
+    const tempProjectDir23 = await fs.mkdtemp(path.join(os.tmpdir(), 'bmad-gemini-test-'));
+    const installedBmadDir23 = await createTestBmadFixture();
+    const legacyDir23 = path.join(tempProjectDir23, '.gemini', 'commands');
+    await fs.ensureDir(legacyDir23);
+    await fs.writeFile(path.join(legacyDir23, 'bmad-legacy.toml'), 'legacy\n');
+
+    const ideManager23 = new IdeManager();
+    await ideManager23.ensureInitialized();
+    const result23 = await ideManager23.setup('gemini', tempProjectDir23, installedBmadDir23, {
+      silent: true,
+      selectedModules: ['bmm'],
+    });
+
+    assert(result23.success === true, 'Gemini setup succeeds against temp project');
+
+    const skillFile23 = path.join(tempProjectDir23, '.gemini', 'skills', 'bmad-master', 'SKILL.md');
+    assert(await fs.pathExists(skillFile23), 'Gemini install writes SKILL.md directory output');
+
+    const skillContent23 = await fs.readFile(skillFile23, 'utf8');
+    const nameMatch23 = skillContent23.match(/^name:\s*(.+)$/m);
+    assert(nameMatch23 && nameMatch23[1].trim() === 'bmad-master', 'Gemini skill name frontmatter matches directory name exactly');
+
+    assert(!(await fs.pathExists(path.join(tempProjectDir23, '.gemini', 'commands'))), 'Gemini setup removes legacy commands dir');
+
+    const result23b = await ideManager23.setup('gemini', tempProjectDir23, installedBmadDir23, {
+      silent: true,
+      selectedModules: ['bmm'],
+    });
+
+    assert(result23b.success === true, 'Gemini reinstall/upgrade succeeds over existing skills');
+    assert(await fs.pathExists(skillFile23), 'Gemini reinstall preserves SKILL.md output');
+
+    await fs.remove(tempProjectDir23);
+    await fs.remove(installedBmadDir23);
+  } catch (error) {
+    assert(false, 'Gemini native skills migration test succeeds', error.message);
+  }
+
+  console.log('');
+
   // ============================================================
   // Summary
   // ============================================================

tools/cli/installers/lib/ide/platform-codes.yaml

@@ -120,8 +120,11 @@ platforms:
     category: cli
     description: "Google's CLI for Gemini"
     installer:
-      target_dir: .gemini/commands
-      template_type: gemini
+      legacy_targets:
+        - .gemini/commands
+      target_dir: .gemini/skills
+      template_type: default
+      skill_format: true
 
   github-copilot:
     name: "GitHub Copilot"

tools/docs/native-skills-migration-checklist.md

@@ -221,6 +221,21 @@ Support assumption: full Agent Skills support. BMAD currently uses a custom inst
 - [x] Implement/extend automated tests — 11 assertions in test suite 22 (config, fresh install, legacy cleanup, .kilocodemodes cleanup, reinstall)
 - [ ] Commit
 
+## Gemini CLI
+
+Support assumption: full Agent Skills support. Gemini CLI docs confirm workspace skills at `.gemini/skills/` and user skills at `~/.gemini/skills/`. Also discovers `.agents/skills/` as an alias. BMAD previously installed TOML files to `.gemini/commands`.
+
+**Install:** `npm install -g @anthropic-ai/gemini-cli` or see [geminicli.com](https://geminicli.com)
+
+- [x] Confirm Gemini CLI native skills path is `.gemini/skills/{skill-name}/SKILL.md` (per [geminicli.com/docs/cli/skills](https://geminicli.com/docs/cli/skills/))
+- [x] Implement native skills output — target_dir `.gemini/skills`, skill_format true, template_type default (replaces TOML templates)
+- [x] Add legacy cleanup for `.gemini/commands` (via `legacy_targets`)
+- [x] Test fresh install — skills written to `.gemini/skills/bmad-master/SKILL.md` with correct frontmatter
+- [x] Test reinstall/upgrade from legacy TOML command output — legacy dir removed, skills installed
+- [x] Confirm no ancestor conflict protection is needed — Gemini CLI uses workspace > user > extension precedence, no ancestor directory inheritance
+- [x] Implement/extend automated tests — 9 assertions in test suite 23 (config, fresh install, legacy cleanup, reinstall)
+- [ ] Commit
+
 ## Summary Gates
 
 - [ ] All full-support BMAD platforms install `SKILL.md` directory-based output