/integrations hub: works with the agent you already use

[stubbi]

Context

Being co-named with the agents and frameworks developers already use is a top growth lever (E2B's real moat). We need a single hub that says "works with the agent you already use," with a matrix and a copy-paste quickstart per tool, mirroring E2B and Daytona docs.

Deliverable

• An /integrations hub page with a matrix across coding agents (Claude Code, opencode, Cursor, Cline, Aider, Gemini CLI, Goose) and frameworks (LangChain/deepagents, OpenAI Agents SDK, smolagents, CrewAI, VibeKit, Vercel AI SDK, Pydantic AI, AutoGen, LlamaIndex).
• A per-tool copy-paste quickstart, marking what works today vs planned (honest status).

Links

• Backed by mitos-run/mitos B1 to B6.
• Relates: #203, #204, #205.

Done when

• The hub is live with the matrix and at least the marquee quickstarts (Claude Code, opencode, LangChain, OpenAI Agents SDK).