Editability, fidelity and native assets

editable preserves usable structure where the backend supports it. Text may remain selectable and fonts embedded, but slide artwork can be rasterised. fidelity prioritises appearance and can outline text or turn pages into pictures. Neither policy guarantees an exact round trip. Unsupported combinations fail explicitly.

Every conversion returns a Report: output paths, backend/version, warnings and losses. A loss can describe rasterisation, font changes, layout, effects, media or unsupported features. Read it before accepting generated material. A route with no reported loss is not proof that arbitrary inputs preserve all features.

Why a folder package?

A .mcruft folder stores native assets alongside a JSON manifest of ordered page references. It avoids inventing a replacement for PDF, PPTX, SVG or PSD. Several document pages can point into one source file. Split and merge change those references; export performs the actual conversion. Optional single-page PDF previews help readers inspect the package.

Assets are copied when saved and are not rewritten by ordinary saves. Derived edits retain provenance. Hashes detect changes but are not authentication. Manifest paths must stay inside the package; absolute paths, parent traversal and symlinks are rejected.

Frames and time-based media appear in the model for later work. Frames are empty in the MVP and are not persisted by manifest schema 1. The specification records the precise package layout and tested conversion boundaries.