Remove TaskAction functionality

[rbren]

This PR removes all TaskAction-related code from the codebase, including:

• Removed tasks.py file containing AddTaskAction and ModifyTaskAction classes
• Removed task action imports and references from:
  • openhands/events/action/__init__.py
  • openhands/events/serialization/action.py
  • openhands/controller/agent_controller.py
  • frontend/src/types/core/actions.ts
  • tests/unit/test_action_serialization.py
  • openhands/agenthub/dummy_agent/agent.py

All tests pass and the code has been formatted according to the project standards.

This should fix the issue where main appears to be broken by the command poetry run python3 openhands/core/main.py -t "do a flip" -d ./workspace/ -c DummyAgent

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To run this PR locally, use the following command:

docker run -it --rm   -p 3000:3000   -v /var/run/docker.sock:/var/run/docker.sock   --add-host host.docker.internal:host-gateway   -e SANDBOX_RUNTIME_CONTAINER_IMAGE=docker.all-hands.dev/all-hands-ai/runtime:3935dfc-nikolaik   --name openhands-app-3935dfc   docker.all-hands.dev/all-hands-ai/openhands:3935dfc

[enyst]

Two notes:

• there are more occurrences, some of those here, such as the schema/action.py file
• but one reference is in the planner agent's prompt:

by using the add_task and modify_task actions described below[...]

FWIW the planner agent did well in a manual test a few days ago.

Edited to add: it can only be tested manually currently.

[tofarr]

🍰 (Once Engle's notes are addressed) - But I think we probably need a follow up PR at some point to check our test coverage

[rbren]

Good catch Engel!

I think it makes sense to ditch the PlannerAgent for now. We can reintroduce it if we make planning a first-class concept again

[enyst]

Good catch Engel!

I think it makes sense to ditch the PlannerAgent for now. We can reintroduce it if we make planning a first-class concept again

There is this PR in progress, I hope it will allow us a cool alternative way of doing it.