* ci: add cross-platform support for E2E and smoke tests
Make headed browser tests (E2E and smoke) runnable on Linux, macOS,
and Windows:
- setup-chrome action: only install xvfb on Linux (macOS/Windows
have native GUI sessions and don't need a virtual display)
- e2e-headed.yml: add OS matrix, use xvfb-run wrapper only on Linux
- ci.yml smoke-test: add OS matrix, use xvfb-run wrapper only on Linux
The browser-actions/setup-chrome action already supports all three
platforms natively.
* ci: exclude Windows from E2E/smoke matrix (Chrome install hangs)
browser-actions/setup-chrome hangs indefinitely during Chrome MSI
installation on Windows runners (observed 10+ min with no progress).
This is a known limitation of Windows CI runners.
Keep Linux + macOS for headed browser tests. Windows is still covered
by build, unit-test, and adapter-test jobs.
## Changes
### E2E Test Suite (~52 test cases)
- public-commands.test.ts — Public API commands (hackernews, v2ex)
- browser-public.test.ts — Browser commands for public data across all sites
- browser-auth.test.ts — Graceful failure verification for login-required commands
- management.test.ts — Full coverage of management commands
- output-formats.test.ts — Output format validation (json/yaml/csv/md)
- smoke/api-health.test.ts — Scheduled API health checks
### Auto-detect Browser Mode
- buildMcpArgs uses CI env var to select mode:
- Local (no CI) → --extension (connect to user's Chrome)
- CI → standalone (launches its own browser)
### CI Pipeline
- e2e-headed.yml — Real Chrome via setup-chrome + xvfb in headed mode
- ci.yml — build + unit-test (2 shards) + smoke-test (scheduled/manual)
- Composite action for shared Chrome + xvfb setup
### Documentation
- New TESTING.md — Architecture, coverage, local setup, how to add tests
Co-authored-by: AlexYue <yj976240184@qq.com>
jakevin