feat: add AIMLAPI provider integration and example

[D1m7asis]

This PR introduces AI/ML API support as a provider in Marvin.

Changes:

• Added AIMLAPIProvider in marvin.providers, extending Pydantic AI’s provider system.

• Registered provider in __init__.py.

• New example: examples/provider_specific/aimlapi/run_agent.py shows how to run an agent with AI/ML API.

• Docs updated:

  • README mentions AI/ML API as a supported provider.
  • Installation guide explains AIML_API_KEY environment variable.
  • Config guide lists AI/ML API among available providers.

Features:

• OpenAI-compatible interface via AI/ML API.
• 300+ models accessible (OpenAI, Anthropic, Google, Meta, Alibaba, etc.).
• Simple usage with marvin.Agent and Pydantic AI models.

Reference: #1171

Screenshot:

[Copilot]

Pull Request Overview

This PR adds support for AI/ML API as a new provider in Marvin, enabling access to 300+ models through an OpenAI-compatible interface.

• Introduces AIMLAPIProvider class that extends Pydantic AI's provider system
• Provides example usage demonstrating how to configure and use the AI/ML API provider with Marvin agents
• Updates documentation to include AI/ML API as a supported provider option

Reviewed Changes

Copilot reviewed 6 out of 6 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/marvin/providers/aimlapi.py	New provider implementation with OpenAI-compatible interface for AI/ML API
src/marvin/providers/init.py	Exports the new AIMLAPIProvider class
examples/provider_specific/aimlapi/run_agent.py	Example demonstrating AI/ML API usage with Marvin agents
docs/installation.mdx	Adds AI/ML API setup instructions including environment variable configuration
docs/guides/configure-llms.mdx	Lists AI/ML API among supported providers
README.md	Updates description to mention AI/ML API support

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[zzstoatzz]

@D1m7asis @OctavianTheI i appreciate the effort going into the PR

i guess i was not anticipating your request in #1171 would require a new providers module

i am not really keen on the new module nor the readme change. it seems like if you're an openai compatible shim for providers, you could use one of the existing providers from pydantic ai and change the base url

why is that not the case? i.e. why not just add an example to examples?