get screenshot from ExtEnv

Here is a environment description of MetaGPT env for different situation.
For now, the code only define the environment and still some todos like migrate roles/actions to current version.

Function

• Define ExtEnv(Base Class) which help users to integrate with external environment like games through apis or construct the game logics.
• Define Environment(Base Class) which is the env that MetaGPT directly used. And it includes roles and so on.
• Define the EnvAPIRegistry to mark the read/write apis that ExtEnv provide observe/step ability. And then, users can call the particular one to get observation from env or feedback to env.

Usage

init environment

android_env = env.create(EnvType.ANDROID)

assistant = Role(name="Bob", profile="android assistant")
team = Team(investment=10.0, env=android_env, roles=[assistant])

observe & step inside role's actions

from metagpt.environment.api.env_api import EnvAPIAbstract

# get screenshot from ExtEnv
screenshot_path: Path = await env.observe(
            EnvAPIAbstract(
                api_name="get_screenshot", kwargs={"ss_name": f"{round_count}_before", "local_save_dir": task_dir}
            )
        )

# do a `tap` action on the screen
res = env.step(EnvAPIAbstract("system_tap", kwargs={"x": x, "y": y}))

TODO

• add android app operation assistant under examples/android_assistant
• migrate roles/actions of werewolf game from old version into current version
• migrate roles/actions of minecraft game from old version into current version
• migrate roles/actions of stanford_town game from old version into current version