Hoists the three feature-specific upload modals out of the artcraft
Tauri host into @storyteller/ui-upload-modal so the website (and any
future host) can render the same flows through PageScene's adapter
slots. Replaces direct `~/Classes/ApiManager` calls with @storyteller/api's
MediaUploadApi/MediaFilesApi.
Removes the old lib-internal UploadModal/UploadFiles/uploadAssets
placeholders (unused) and inlines the host-local enums
(MediaFileAnimationType, UploaderState/States, file-type enums) into
Types.ts. Adds UploadSpzFile to @storyteller/api's MediaUploadApi and
the SPLAT variant to FilterEngineCategories.