Add lastAccessedAt timestamp to nodes with schema migration and
backfill. Touch timestamp on read, apply exponential freshness decay
(~69-day half-life) to search scoring alongside BM25 and vector
weights. Add auto-decay that marks untouched nodes as stale after a
configurable threshold, with CLI command and server-side daily interval.
Include comprehensive USAGE.md documenting all CLI commands and REST API.
Express API server wrapping existing store/graph core with REST endpoints
for nodes, edges, graph, and search. React + Vite portal with React Flow
for interactive graph visualization, Tailwind CSS styling, and full CRUD UI
(sidebar, node panel, add/link modals, search bar, toast notifications).
