expose context key info command, add first version of completion item provider for package.json and keybindings.json files, https://github.com/microsoft/vscode/issues/9303

This fixes the tree view rpc test
Fixes #116776

add NotebookCellOutput#metadata, also use API type internally and translate dto sooner, fixes https://github.com/microsoft/vscode/issues/116792

now that the coloring is easier to differentiate

Ref https://github.com/microsoft/vscode/issues/114653

Fixes #115017

Fixes #114991

Fixes #116589

Fix: wrong event for `onDidSaveNotebookDocument`

Fix misspelling of "likelihood"

Per https://github.com/microsoft/vscode/pull/116728#pullrequestreview-590976270.

Fixes #116775

allow to exclude a context key from registry, allow to provide type eplicitly, https://github.com/microsoft/vscode/issues/114867