v0.3.0

Added

• Static HTML dashboard (vectl dashboard) with Overview and DAG views.
• Dashboard data serializer and single-file HTML generator.
• Dashboard test suite: unit tests + Playwright UI tests (opt-in via -m playwright).

Fixed

• Phase/step click interactions (event binding after dynamic render).
• Step table dependency column alignment.

Docs

• README (EN/ZH): document vectl dashboard usage.