Offline-first platform specification pack

This folder contains the expanded platform specification for disconnected clients and synchronization.

Document	Purpose
SPEC.md	Functional and non-functional requirements (FR-OFF / NFR-OFF)
TECHNICAL_REQUIREMENTS.md	Technical requirements (TR-OFF), reference implementation notes
SOLUTION_DESIGN.md	Architecture and sequence diagrams
TRACEABILITY_MATRIX.md	Traceability and module adoption phases

The short normative spine remains OFFLINE_FIRST_AND_CLIENT_SYNC.md.