Reading Library V4.9.6 — Discover search improvements

- Combines Catalogue Manager synonym/partial matching with field-weighted Reading Library search.
- Indexes title, topic, description, family, resource type, keywords, tags, reading skills and additional catalogue metadata aliases.
- Supports compound reading skills such as main idea / central idea / summarising as concepts.
- Prioritises exact title and verified keyword matches, while retaining grade, genre, category, Free and owned filters.
- Shows clearly labelled broader reading resources if the currently published catalogue contains no exact skill keywords.
- Preserves the V4.9.5 home promotions, Blackthorn reward, YouTube page and newsletter.
- No automatic changes to the publisher's catalogue metadata or website.

Important: the bundled catalogue (783 entries) predates recent skill metadata. Publishers must publish an updated Catalogue Manager export to get genuine main-idea matches.
