Allow agent to run compound tasks

[meganrogge]

Because we filter out tasks without a type here, our compound tasks (build tasks) are filtered out.

We should check if task.type || task.dependencies.length I think here instead:

https://github.com/microsoft/vscode-copilot-chat/blob/c41a3eb66f2695c27d354a590f4ee68b1e33f660/src/extension/prompts/node/agent/agentPrompt.tsx#L564

cc @connor4312