[Ri0n]

Changes

• Accept local file URLs in all desktop editor shells, including the manager, standalone notes and embedded editor.
• Import mixed selections of files as one ordered asynchronous batch through LocalMediaStore; keep image/audio/video as inline media and render other MIME types as attachment blocks.
• Use encrypted copy-on-drop, preserve internal structured image drag behavior, and group each drop into one undoable operation.
• Add regression tests for opening an existing serialized attachment in desktop QML and accepting mixed file-manager URL drags; reject directories, nonexistent files and nonlocal URLs.

Verification

• Source reviewed against existing editor/model ownership and MIME handling.
• Local Qt toolchain is not available in this environment; awaiting CI results.

Note: current attachment Markdown codec and QML block renderer are already implemented, so the rendering regression test checks that full path explicitly.

MIME file card presentation

• Show localized file type names from Qt's QMimeType::comment() in place of raw MIME identifiers.
• Use MIME-specific theme icons (with genericIconName() fallback) instead of a paperclip; fall back to a bundled generic document icon when no system icon is available.
• Handle absent/generic MIME types using the filename extension without fetching remote files.
• Add editor QML and icon-provider regression coverage.