tasks.json

{
  "version": "2.0.0",
  "tasks": [
    {
      "label": "watch",
      "detail": "tsc -p ./ --watch — background compile for the Run Extension launch config",
      "type": "shell",
      "command": "npx tsc -p ./ --watch",
      "options": { "cwd": "${workspaceFolder}" },
      "isBackground": true,
      "problemMatcher": "$tsc-watch",
      "presentation": { "reveal": "never", "panel": "dedicated" },
      "group": { "kind": "build", "isDefault": true }
    },
    {
      "label": "compile",
      "detail": "tsc -p ./ — one-shot build into out/",
      "type": "shell",
      "command": "npx tsc -p ./",
      "options": { "cwd": "${workspaceFolder}" },
      "problemMatcher": "$tsc",
      "presentation": { "reveal": "silent", "panel": "dedicated" },
      "group": "build"
    }
  ]
}