Support more providers

[mtth]

In particular those that are specialized for editing code, and have built-in file editing functionality.

SDK-related links:

• https://docs.anthropic.com/en/docs/agents-and-tools/tool-use/overview
• https://docs.anthropic.com/en/docs/claude-code/sdk
• https://github.com/anthropics/claude-code-sdk-python/blob/main/src/claude_code_sdk/types.py
• https://github.com/openai/codex