Add Agents Support to SDK

[tmichaeldb]

Fixes RAG-26.

Depends on changes in #9067

This PR adds support for creating & using agents from underlying MindsDB Langchain models. Currently, only text-to-SQL is supported. A follow-up PR will add a retrieval skill for RAG functionality.

See /examples/using_agents.py for example usage:

import mindsdb_sdk

con = mindsdb_sdk.connect()

# We currently support Langchain as a backend.
print('Creating underlying langchain model for the agent to use...')
try:
    langchain_engine = con.ml_engines.get('langchain')
except Exception:
    # Create the engine if it doesn't exist.
    langchain_engine = con.ml_engines.create('langchain', handler='langchain')

# Actually create the underlying model the agent will use.
langchain_model = con.models.create(
    'agent_model',
    predict='answer',
    engine='langchain',
    prompt_template='You are a spicy, cheeky assistant. Add some personality and flare when responding to the user question: {{question}}',
    model_name='gpt-4-0125-preview' # This is the underlying LLM. Can use OpenAI, Claude, local Ollama, etc
    # Can optionally set LLM args here. For example:
    # temperature=0.0,
    # max_tokens=1000,
    # top_p=1.0,
    # top_k=0,
    # ...
)
print('Agent ready to use.')

# Now create an agent that will use the model we just created.
agent = con.agents.create('new_agent', langchain_model)
print('Ask a question: ')
question = input()
answer = agent.completion([{'question': question, 'answer': None}])
print(answer.content)

[tmichaeldb]

Note streaming responses will be tracked by this issue. https://linear.app/mindsdb/issue/RAG-22/update-api-endpoints-to-fully-support-agents

We need to add streaming support to our underlying API

[ea-rus]

I've merged #97. Now if you update this branch from staging - CI should be fine

[tmichaeldb]

Ready for another round of reviews. Tests are passing locally for me (looks to be only failing on 3.7)

[github-actions]

Coverage Report

File	Stmts	Miss	Cover	Missing
mindsdb_sdk
agents.py	87	18	79%	16, 75, 78, 82, 84, 86, 88, 90, 166–168, 189–191, 195–199
databases.py	42	2	95%	107, 134
handlers.py	39	1	97%	77
jobs.py	65	3	95%	96–99
ml_engines.py	42	3	93%	94, 126, 128
models.py	181	13	93%	107, 195, 204, 206, 276, 308, 336, 457, 465, 484, 500, 527, 531
projects.py	59	1	98%	162
query.py	13	1	92%	14
skills.py	44	4	91%	43, 45, 49, 107
tables.py	108	4	96%	177, 189, 205, 297
views.py	37	2	95%	105, 138
mindsdb_sdk/connectors
rest_api.py	161	19	88%	16–26, 32–33, 48, 69–71, 88, 91, 98–101
TOTAL	950	71	93%

Tests	Skipped	Failures	Errors	Time
14	0 💤	0 ❌	0 🔥	8.417s ⏱️

[ea-rus]

I've added some fixes for tests and docs, CI works now

[dusvyat]

nice looks good to me