Merge pull request #59 from CloudNativeAI/add-media-type-untested-anno

feat: add untested media type annotation to annotations.md

Author: BraveY

docs/annotations.md

@@ -10,6 +10,8 @@ This property contains arbitrary metadata, and SHOULD follow the rules of [OCI i
 
 - **`org.cnai.model.file.metadata+json`**: Specifies the metadata of the file (string), value is the JSON string of [File Metadata Annotation Value](#File-Metadata-Annotation-Value).
 
+- **`org.cnai.model.file.mediatype.untested`**: Indicates whether the media type classification of files in the layer is untested (string). Valid values are `"true"` or `"false"`. When set to `"true"`, it signals that the model packager has not verified the media type classification and the type is inferred or assumed based on some heuristics.
+
 ### Layer Annotation Values
 
 #### File Metadata Annotation Value