feat: add context-aware lecture profiles

[879568078-commits]

Summary

• Add persisted lecture context settings with natural lecture and general modes.
• Add a Treaty Reform in the EU preset plus user-defined terminology.
• Add an MIT license and a Chinese installation, configuration, and troubleshooting guide.

Motivation

VoxBridge needs classroom-aware recognition that follows a law professor's natural delivery without forcing ordinary speech into rigid legal phrasing. This change provides a focused EU treaty reform profile while preserving the existing realtime subtitle revision pipeline, and documents how users can install and operate it.

Changes

• Extend the active Profile domain with normalized interpretation context settings.
• Add an EU treaty reform correction policy for stable subtitles.
• Use context depth to control SubtitleBuffer's recent-segment revision window.
• Apply context correction before stable subtitle updates enter SubtitleBuffer.
• Add bilingual Settings UI controls for mode, topic, revision depth, automatic correction, and custom terms.
• Add domain, policy, and Settings UI tests.
• Add an MIT License for Hanjie Deng and link a Chinese user guide from the README.

Validation

• 106 Vitest tests passed.
• TypeScript typecheck passed.
• ESLint passed for all changed files.
• Production Vite/Nitro build passed.
• README documentation and license links verified.

Notes

• General mode disables the EU course preset.
• Corrections intentionally run only on final or revised subtitle updates, so partial captions remain low-latency and natural.
• This PR performs conservative post-recognition normalization and does not send terminology hints to the AST provider.
• Real interpretation still requires a valid Volcengine AST API key; API quotas are not bundled with VoxBridge.