Task: Implement the AppImage Integration feature

TASK-DESCRIPTION

• Create sources/integration/appimage_integrator.h.
• Create sources/integration/appimage_integrator.cpp.
• Create sources/tools/appimage_integrate.cpp.
• Create scripts/program-install.sh and wire make install.
• Create the sandbox test tests/integration_plan_test.cpp and its runner tests/70-integration-sandbox.sh.
• Create the provenance runner tests/80-desktop-provenance.sh.
• Implement the requirements in prompts/features/09-appimage-integration.md.
• Run make test from the repository root.

TASK-OUTPUT

• Report the created and modified files and the result of make test.

TASK-CONTEXT

• Feature requirements: prompts/features/09-appimage-integration.md.
• Best practice: documents/10-appimage-desktop-integration.md.
• Every test must run under a temporary $HOME; the real desktop must not be touched by a test.
• The installed tools live in $HOME/.local/bin, so launcher actions have a stable target.

TASK-FILES

• sources/integration/appimage_integrator.h — new
• sources/integration/appimage_integrator.cpp — new
• sources/tools/appimage_integrate.cpp — new
• scripts/program-install.sh — new
• tests/integration_plan_test.cpp — new
• tests/70-integration-sandbox.sh — new
• tests/80-desktop-provenance.sh — new
• sources/CMakeLists.txt — existing
• Makefile — existing