Reading Library V4.8.1 — Smart Studio Installer (experimental)

Based on Reading Library V4.8.0, with no changes to the published catalogue or the registered Headless Horseman resource.

- Studio ZIP automatically extracts to System/studios/PRODUCT_ID when a previously authorised Library folder handle is available.
- First-time Studio installation is reduced to choosing the Library folder once.
- The selected folder is stored locally using IndexedDB and revalidated before reuse.
- Studio detail page now emphasises Open Teacher Mode when ready and Finish Setup when not ready.
- Advanced manual installation and ZIP download remain available.
- The Library checks required files and blocks unsafe extraction paths/oversized ZIPs.
- Normal reading resources, the assessment system and Catalogue Manager verification stay unchanged.

Local ZIP extraction tests passed. Physical browser folder-picker behaviour requires validation on end-user devices.
