* initial wip in the extension host

* wip

* wip

* wip

* continued progress

* update api from discussion

* update for new proposal

* wip

* update to lastest testing api, almost everything working

Refs https://github.com/microsoft/vscode/issues/115089
Design https://gist.github.com/connor4312/73f1883d720654834b7fd40550d3b6e0

* re-wire retirement state

* update actions to new async test structure

* minor cleanup

* remove unused es2018 that failed build

For #119515

Fixes #119500

Fixes #119472

Closes #118603

Fixes Extension Feature Contributions doesn't render markdownDescription

Part of #112675

Implement new execution task API
#106744
Fix #105847

Fix terminal panel not being focused on first create after reload