journal: export, merge --json, progress hook, archive validator (L1 plumbing)
L1 of the convey journal-merge feature.
- sol call journal export — portable ZIP of the active journal with a manifest
- sol call journal merge --json — single-line JSON envelopes, suppresses logging
- merge_journals(progress=...) — optional callback per phase/item
- think/importers/journal_archive.py — read-only validate_journal_archive(zip_path)
Background-importer (L2) and convey UI (L3) compose on these.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>