feat(browser-automation): add playwright-cli as browser automation provider

- Add playwright-cli to BrowserAutomationProviderSchema enum
- Add playwright-cli to BuiltinSkillNameSchema
- Create playwrightCliSkill with official Microsoft template
- Update skill selection logic to handle 3 providers
- Add comprehensive tests for schema and skill selection
- Regenerate JSON schema

Closes #<issue-number-if-any>

src/features/builtin-skills/skills/index.ts

@@ -1,4 +1,5 @@
 export { playwrightSkill, agentBrowserSkill } from "./playwright"
+export { playwrightCliSkill } from "./playwright-cli"
 export { frontendUiUxSkill } from "./frontend-ui-ux"
 export { gitMasterSkill } from "./git-master"
 export { devBrowserSkill } from "./dev-browser"