Provide an anonymizable read-only view

[ap--]

Things that should be potentially anonymizable:

• [ ] Images (include removal of associated images)
• [ ] Image Metadata
• [ ] Metadata Columns
• [ ] Annotation Metadata
• [ ] Store user_metadata

[ap--]

Images: https://github.com/libvips/pyvips/issues/307 pyvips 8.13 supports fsspec compatible IO