aae8d0a379
In-progress work committed to unblock the config import/export plan: - prompts: FILE_REFERENCES section for workspace-relative file citation - backends: resolve quoted virtual absolute paths onto the sandbox workspace - middleware: read_file_images middleware; message_budget extensions - image_gen/model_registry: image model 'enabled' flag refactor - memory/launch, gateway/background_runs, tools/image follow-ons - scripts: dev_backend.sh, release.sh - tests for the above