feat: add MiniMax M3 provider

[Octopus (octo-patch)]

Summary

Add MiniMax as an LLM provider option, defaulting to MiniMax-M3 on the international OpenAI-compatible endpoint while supporting editable OpenAI-compatible and Anthropic-compatible endpoints.

Changes

• Register minimax across the shared schema, provider UI, and server factories
• Add MiniMax-M3 and MiniMax-M2.7 with their current context windows and supported capabilities
• Support the global and China OpenAI-compatible and Anthropic-compatible endpoints through the editable base URL
• Route /anthropic base URLs through the Anthropic SDK while keeping the documented base URL unchanged
• Link the official API overview from the provider form
• Add unit coverage for provider creation, templates, the model catalog, and endpoint request routing

Testing

• bun test apps/app/screens/ai-settings/models.test.ts apps/app/lib/llm-providers/providerTemplates.test.ts apps/server/tests/lib/clients/llm/provider.test.ts
• bun test scripts/generate-models.test.ts
• bun run --filter @browseros/app test
• bun run --filter @browseros/server test:lib
• bun run --filter @browseros/server test:agent
• bun run check

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[Octopus (octo-patch)]

#1540

[Octopus (octo-patch)]

I have read the CLA Document and I hereby sign the CLA

[Octopus (octo-patch)]

Updated the MiniMax adapter to route /anthropic base URLs through the Anthropic SDK while preserving /anthropic as the user-facing base URL. I added request-capture coverage for the global and China OpenAI-compatible and Anthropic-compatible endpoints, and ran the app, server lib, server agent, model generation, and root check suites.