feat(model): add MiniMax provider support

[octo-patch]

Reason: add the target provider and models to the existing provider registry.

Type of Change

New Feature

Description

• Registers MiniMax-M3 and MiniMax-M2.7 with their model metadata.
• Adds global and China API hosts for both supported compatibility protocols.
• Selects the protocol adapter from the configured API Host value.
• Adds model settings labels, configuration guidance, and request-routing tests.

Testing

• uv run pytest valuecell/adapters/models/tests/test_minimax_provider.py -q
• uv run pytest -q
• uv run ruff check .
• uv run ruff format --check valuecell/adapters/models/factory.py valuecell/adapters/models/__init__.py valuecell/config/manager.py valuecell/server/api/routers/models.py valuecell/adapters/models/tests/test_minimax_provider.py
• bun run lint
• bun run typecheck
• bun run build

Checklist

• I have read the Contributing Guidelines.
• My changes follow the project coding style.
• I have added relevant tests.