Add impact index fixture and filesystem artifact uploader

- Introduced a sample BOM index JSON file for impact index testing.
- Created unit tests for the impact index fixture to ensure proper loading of sample images.
- Implemented the FilesystemPackRunArtifactUploader class to handle artifact uploads to the local filesystem.
- Added comprehensive tests for the FilesystemPackRunArtifactUploader, covering file copying, missing files, and expression outputs.

deploy/compose/env/airgap.env.example

@@ -27,6 +27,10 @@ SCANNER_EVENTS_DSN=
 SCANNER_EVENTS_STREAM=stella.events
 SCANNER_EVENTS_PUBLISH_TIMEOUT_SECONDS=5
 SCANNER_EVENTS_MAX_STREAM_LENGTH=10000
+SCANNER_SURFACE_FS_ENDPOINT=http://rustfs:8080/api/v1
+SCANNER_SURFACE_CACHE_ROOT=/var/lib/stellaops/surface
+SCANNER_SURFACE_SECRETS_PROVIDER=file
+SCANNER_SURFACE_SECRETS_ROOT=/etc/stellaops/secrets
 SCHEDULER_QUEUE_KIND=Nats
 SCHEDULER_QUEUE_NATS_URL=nats://nats:4222
 SCHEDULER_STORAGE_DATABASE=stellaops_scheduler