Shared utilities
Source: src/app/shared
Shared code provides cross-cutting support used by multiple layers: logging and startup configuration, shared exceptions, image/frame helpers, box serialization, masked blur primitives, and distribution/resource utilities. These helpers support the application but do not own session workflows or domain policy.
Keep additions small, stable, and broadly reusable. Session and workflow decisions belong in Application, core types and rules in Domain, and widget-specific helpers in UI. For example, shared masked-blur primitives are consumed by both preview and export code, while annotation import/export orchestration remains in Application services.