Mino chapter-06

Added

• Chapter 06 combines manual /compact and automatic context compaction. Keep
  the latest two replayable turns and all active tool steps; summarize earlier
  complete turns with the previous summary and preserve original JSONL records.
• Optional context_window in ~/.mino/config.json: default 128,000 tokens,
  overridden by a positive integer. Startup reports the value/source without
  querying model metadata. Omitted or zero uses the default; invalid values fail.
• Conservative serialized-byte context estimates, output reservation (one eighth
  of the window, capped at 8,192 tokens), and an automatic trigger above 80% of
  the remaining input budget. Check every request, including after tool results;
  one automatic summary per turn counts toward the existing eight-request limit.
• Persist summaries and covered whole-turn boundaries before using them; restore
  them on restart/resume and remove them with confirmed /clear. Tool-free
  summary requests retain source/uncertainty instructions and cannot authorize
  tools. Failed or non-shrinking summaries retain the old context; oversized
  requests fail without silent truncation or command retries.

Changed

• Write history record version 3 while reading versions 1–3. Older releases cannot
  read new records; retain private backups before upgrading if rollback is needed.
• Set an explicit output-token limit and disable server truncation on Responses
  requests. The local estimate is deliberately conservative, not exact tokenization.
• Update the default SOUL and terminal help. Existing SOUL files stay untouched.