[Enhancement] Support quick pick to select target stack when compile/preview/apply/destory

Enhancement

The extension now supports trigger compile/preview/apply/destroy/.. operation by two ways:

1. right clicking on the active editor and select operations in the editor context menu.
2. open the command palette and type "Kusion: ${OperationName}"
   When the active document does not belongs to a stack, a "not in a stack" error message will pop up.

In order to support quickly applying/previewing/... one or more stacks' configuration, when the operation is triggered by the command palette, a quick pick stack list should be provided for users to filter and select.

The probable interaction would be like this:

or if we allow to batch operate multiple stacks in the future:

requirement

https://github.com/KusionStack/KCLVM/issues/446

• requires Kusion provide API to analyze the konfig workspace and recognize all the stack/projects:
  • ListProject(workspaceRoot: string): []Project
  • ListStacks(workspaceRoot: string): []Stack

Start by reviewing the command-palette handlers for compile, preview, apply, and destroy, then check the KCLVM requirement for ListProject and ListStacks. The work is done when a command-palette operation can obtain workspace stacks and present a quick pick for filtering and selecting a target stack.