v0.3.1

Changed

• remember, inspect_codex_item and review_codex are faster on large
  stores. Belief vectors for proximity checks are decoded once per connection
  and refreshed when the database changes, lineage is resolved in one recursive
  query instead of one query per step, and status and trend summaries read only
  the columns they need. At 10,000 beliefs p95 drops from 30-55 ms to under
  20 ms. Results, ordering and the schema are unchanged.
• npm run check:deps uses the shared zero-dependency check (manifest and
  packed tarball) and runs as its own CI and release step.
• Added AGENTS.md with contributor guidance.

Full Changelog: v0.3.0...v0.3.1