Fix Conversation Memory Autoload

[collindutter]

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Describe your changes

Refactors Conversation Memory to support using a Driver set in Structure Config. For instance:

from griptape.config import OpenAiStructureConfig
from griptape.structures import Agent
from griptape.memory.structure import ConversationMemory
from griptape.drivers import LocalConversationMemoryDriver

agent = Agent(
    config=OpenAiStructureConfig(
        conversation_memory_driver=LocalConversationMemoryDriver(),
    ),
    conversation_memory=ConversationMemory(),
)

agent.run("My name is Collin")
agent.run("What is my name")

Issue ticket number and link

NA

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📚 Documentation preview 📚: https://griptape--1033.org.readthedocs.build//1033/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

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[vachillo]

should the strucuture just set the driver rather than setting the structure itself? also why the hasattr? should it just default to None?

[collindutter]

This pattern is easier to apply to other areas of the framework (tasks) if the Structure sets itself.

init=False because we don't want users to set the Structure, it should only be done by the Structure itself.

[dylanholmes]

Love the bug fixes

Just one comment/question

[dylanholmes]

Feels to me like this autoloading decision should be made from within the conversation memory class. Like either in the structure setter, or in another method called maybe preprocess (if we wanna be consistent with the way tasks are added to structures)

Also, won't load() get called twice? (Once in the __attrs_post_init__, when there is no structure, then once here after the structure is added) Is that ok?

[collindutter]

Should be fixed by #1045