Keep Amiga-specific files under amiga/, cache the pinned LHa binary in
CI, and make it explicit that the workflow artifact is not an official
release.
Co-authored-by: Cursor <cursoragent@cursor.com>
The meson workflow only builds and tests across platforms; none of its
jobs write to the repository, packages, or other GitHub resources. Add a
workflow-level `permissions: { contents: read }` block so the default
GITHUB_TOKEN follows least privilege instead of inheriting the broad
read/write scopes granted by default.