state provider for @beta_tool and @async_beta_tool

[marwq]

Currently the only way to provide a request-scope state for tools in the beta runner is a wrapper:

def setup_tools(user_id: int):
    @beta_tool(name='get_user')
    def get_user(id: int) -> str:
        if user_id != id:
            return 'Error: User doesn't have permission'
        return ...

    return [get_user]

# in router/interactor
user_id = 123
client.beta.tool_runner(
    ...,
    tools=setup_tools(user_id)
)

I suggest to add feature for passing context for tools:

@beta_tool(name='get_user')
def get_user(id: int, ctx: Context) -> str:
    if ctx['user_id'] != id:
        return 'Error: User doesn't have permission'
    return ...

client.beta.tool_runner(
    ...,
    tools=[get_user],
    context={'user_id': 1},
)

Or at least support for methods:

class FetchProduct
    def __init__(self, ctx: dict):
        self.ctx = ctx

    @beta_tool(name='fetch_product')
    def __call__(self, id: int) -> str:
        return self.ctx['session'].get(Product, id)

tools = [FetchProduct(ctx)]

Currently, it doesn't work because an error would be raised on the self argument.

[marwq]

Also I suggest considering of dishka or fastdepends dependency injection support for the tool runner and tools.