feat: Make openFile experience consistent with built-in trees

[xqzlgy2]

This PR changes two parts:

1. From VS Code 1.52, all custom tree behavior has been changed, which enable our plugin to have more consistent experience with file explorer when open file. That means, all following interactions are enabled for fileNode and primaryTypeNode:

• Double-click or mouse-middle-click to open in non-preview.
• Enter to open in non-preview mode (Space to open in preview mode).
• Alt+Click to open an editor to the side of the active one.

reference: https://code.visualstudio.com/updates/v1_52

2. Since changes above needs to register vscode.open as TreeItem's command id, we can not use customized java.view.package.openFile command to send telemetry. As compensate, we send these additional info in telemetry:

• {projectManagerVisible: 1} when project manager is expanded
• counter for didChangeSelection, didCollapseElement, didExpandElement events

[jdneo]

I think we need also update the vscode engine version to 1.52.0 to limit the impact.

[jdneo]

Thanks @xqzlgy2