What's Changed
* fix: lookup table problems by ngjaying in https://github.com/lf-edge/ekuiper/pull/2961
* refactor(io): move extended plugins by ngjaying in https://github.com/lf-edge/ekuiper/pull/2964
* feat(js): restore js functions by ngjaying in https://github.com/lf-edge/ekuiper/pull/2965
* feat: support httppull incremental by Yisaer in https://github.com/lf-edge/ekuiper/pull/2962
* feat: restore native plugin manager by ngjaying in https://github.com/lf-edge/ekuiper/pull/2967
* feat: support rest sink by Yisaer in https://github.com/lf-edge/ekuiper/pull/2966
* fix(lookup): no return for empty result by ngjaying in https://github.com/lf-edge/ekuiper/pull/2971
* feat(plugin): restore sample plugins & ut by ngjaying in https://github.com/lf-edge/ekuiper/pull/2973
* feat: support httppush source by Yisaer in https://github.com/lf-edge/ekuiper/pull/2968
* refactor(contract): function exec ctx arg first by ngjaying in https://github.com/lf-edge/ekuiper/pull/2976
* feat: support websocket socket source by Yisaer in https://github.com/lf-edge/ekuiper/pull/2980
* feat(graph): restore graph api by ngjaying in https://github.com/lf-edge/ekuiper/pull/2979
**Full Changelog**: https://github.com/lf-edge/ekuiper/compare/v2.0.0-alpha.6...v2.0.0-alpha.7