@isaacs/ttlcache has no byte cap (only count). A 100MB hard limit needs
lru-cache v10's maxSize + sizeCalculation. Aligns design spec with
Phase 1 master plan contract revision.
Captures the dual-mode Modern.js architecture, strangler-fig phasing,
parity contracts, and customer-requirement mapping so implementation
plans can be derived per phase without re-litigating architectural
decisions.
gnezim