Development record

`.abcd/development/brief/05-internals/07-memory.md:185-189` gives three brackets. `internal/core/rules/brackets.go:79-85` has four: an unknown row applies when no source gives the fill and sends pages as one line each. MODERATE sends the top-ranked pages in full up to 8 KiB and the rest as one line each. DEPLETED's lines come from each page's own summary, not `index.md` (`internal/core/memory/recallpages.go:26-27`, `internal/core/recall/pages.go:2`), which also makes :193's query of `index.md` wrong. MODERATE and DEPLETED also shrink the rules to a heading and first rule, which the chapter never says.