Add workflow_dispatch-triggered workflow that builds and pushes images
to GitHub Container Registry (ghcr.io). This allows forked repositories
to build their own images for testing without requiring Docker Hub
credentials.
Images are tagged with branch names, semver tags, and commit SHA for
easy testing of specific builds.
Signed-off-by: dtinth on MBP M1 <dtinth@spacet.me>
Add support for the `AWS_S3_SIGNATURE_VERSION` environment variable to
allow configuring S3 signature version for compatibility with
S3-compatible storage services like Linode Object Storage.
Fixes#1788
Signed-off-by: dtinth on MBP M1 <dtinth@spacet.me>