Fix long OpenCode prompt completion

[crankshift]

Summary

• Use OpenCode async prompt admission when event streaming is available so long research/subagent runs do not depend on a held HTTP prompt response.
• Resolve Telegram replies from the matching completed assistant message event, with opencode.promptTimeoutMs as the completion deadline.
• Update release metadata and docs for 0.11.1.

Test Plan

• pnpm run lint
• pnpm test
• pnpm run check

Closes #53