Lists the documents under doc/ in four sections so a reader can
find their way to the right page without grepping the tree:
- Architecture & design: Architecture.md (root) + the seven
per-topic pages under doc/architecture/.
- Roadmap & design exploration: ROADMAP.md (at the repo root)
and doc/ddd-exploration-2026-06-14.md.
- Samples: doc/offer-sample.md.
- Work journal: doc/dev-tracking/* (informal, not published).
Each entry has a one-line description so the table is scannable
on its own.
