v2.1.311

Claude Code v2.1.311 adds --hold-idle-file and --max-hold-min to self-hosted-runner, fixes startup freezes with long CLAUDE.md list items, and resolves standard-context sessions stopping with "Usage credits required for 1M context" by compacting and continuing. It also fixes Write/Edit stalls on large files, subagent MCP tool access, stale MEMORY.md/CLAUDE.md after compaction, and numerous MCP, rewind, IDE, and cloud session issues, plus changes ultrathink to run at xhigh effort on Opus 5.5, Sonnet 5.5, Haiku 5.5 and Fable 5.1 via Anthropic's API.