Localize setup MCP catalog descriptions

[w287346141]

Summary:

• Localized setup wizard MCP catalog summaries and notes through the existing i18n system.
• Kept the underlying MCP catalog entries unchanged for non-wizard callers.
• Added wizard coverage for zh-CN MCP catalog descriptions.

Verification:

• npm.cmd run test -- wizard.test.tsx passed
• npm.cmd run typecheck passed
• Manually ran npm.cmd run dev -- setup and confirmed MCP descriptions show in Chinese after selecting 简体中文

[w287346141]

Superseded by #21, which batches the setup wizard localization work and resolves the shared Wizard.tsx / tests/wizard.test.tsx conflicts ahead of review.