Connect to Debug Target

[tsmaeder]

This epic represents the minimal demoable feature for the debug protocol Theia debugger. The scenario we'd like to implement is the following:

1. In Theia, invoke an action that allows to connect to a preexisting debug target
2. With the help of some user input, the debugger connects to said target
3. The connected debug target shows up in a UI with identifying information
4. The user disconnects from the debug target

[tsmaeder]

Steps to achieve this goal:

• Implement contribution API for debug adapters

• Implement Contribution API for Debug Adapters #8953
  see https://code.visualstudio.com/docs/extensionAPI/api-debugging, adapt style to Theia (example, language servers),
  • need network forwarder for protocol because of client/server split: debug adapters run on backend, client is on front end
  • discover debug adapters
  • contribute configuration for "connect" request

• Create contribution for NodeJS debug adapter

• Create contribution for NodeJS debug adapter  #8954
  https://github.com/Microsoft/vscode-node-debug

• Implement an action to connect to a nodejs instance with a given port

• Connect Debugger to NodeJS #8955
  • detect that "nodejs" adapter is present
  • create UI to populate "connect" parameters
  • send "connect" request to adapter

• Show Debug Sessions

• Show Debug Sessions #8956

• Implement action to send "disconnect" to debug target

• Disconnect from Debug Session #8957