AstraBridge v0.4.2

AstraBridge 0.4.2

• Add Grok 4.7 support to AstraBridge Runner through the xAI Responses API and
  XAI_API_KEY, alongside ChatGPT and DeepSeek.
• Support native game tools, automatic screenshots, streaming responses,
  encrypted reasoning, checkpoint compaction and session resume with Grok.
• Adapt exported tool schemas to xAI requirements while preserving the original
  argument validation. Include separate reasoning usage in context accounting
  and preserve the session's prompt cache key across resume.
• Package AstraBridge Runner 0.1.2 and update its setup documentation.