feat(PLU-325): migrate collection search to v3 endpoints and bump SDK

[robertmarsal]

• Migrate collection search from v2 SearchApi.search_collections to v3 CollectionsApi.v3_list_collections, removing all v2 collection endpoint usage
• Bump revengai SDK floor to 3.123.0
• Remove dead legacy _search_items code that still called v2 collection endpoints
• Show the collections/binaries popups modally via open() and fire the field event filter once, so selecting a collection no longer tears down the matching dialog
• Connect the collections table signals once and populate under blockSignals to stop the disconnect RuntimeWarnings
• Trim verbose per-item logging in the search and data-type paths
• Update SDK schema tests for the v3 collections API