AppImage runtime pin missing or unavailable

The linux-appimage package requires a separately prepared, hash-pinned AppImage runtime. The preset or doctor check could not find the required pin or its local source.

#Common causes

• appimageRuntime is absent from the preset, or its source is unavailable.

#Fixes

• Obtain an x86_64 type-2 AppImage runtime as an explicit setup step and run ara-export artifact-pin --file <runtime>.

• Put the resulting hash and source in appimageRuntime, then run doctor with the preset. The runtime is not a Cargo build prerequisite.

• Code: ARA-EXP-APPIMAGE-001 (slot 8093)

• Constant: export::APPIMAGE_001

• Reported by: ara-export