library: add Quick Add page (scan an ISBN, the book is added)

A small standard-library Python service next to Koha:
- looks the code up via Z39.50 (yaz) then Open Library over HTTPS
- checks Koha for an existing copy (ISBN-10/13 and UPC/EAN aware)
- adds the record + an item with the next barcode via Koha's REST API
- scanner-friendly UI: auto-focus, audible feedback, duplicate card with
  'add another copy', manual entry when nothing is found, undo, and the
  barcode range to print labels for
Also: enable RESTBasicAuth, map 024$a to the ean column, wire the service,
port and credentials into compose/install.sh.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013wi3ZSot4XbUViwRFgLpRf

library/koha/bootstrap.pl

@@ -96,10 +96,17 @@ $admin->set_password({ password => $env{admin_pass}, skip_validation => 1 });
 $dbh->do(q{UPDATE marc_subfield_structure SET defaultvalue = 'BOOK'
            WHERE tagfield = '942' AND tagsubfield = 'c'});
 
+# UPC/EAN barcodes (DVDs, CDs, games) live in 024$a, which the stock framework
+# leaves unmapped - so Koha can neither search nor de-duplicate on them. Map it
+# to the catalogue's `ean` column (used by the quick-add page's duplicate check).
+$dbh->do(q{UPDATE marc_subfield_structure SET kohafield = 'biblioitems.ean'
+           WHERE tagfield = '024' AND tagsubfield = 'a' AND (kohafield IS NULL OR kohafield = '')});
+
 # ---- Preferences ----------------------------------------------------------
 my %prefs = (
     autoBarcode              => 'incremental',  # new items get a barcode automatically
     itemcallnumber           => '082ab',        # Dewey call number copied from the MARC record
+    RESTBasicAuth            => 1,              # lets the quick-add page use the REST API
     OpenLibraryCovers        => 1,              # cover images in the catalogue
     OPACSearchForTitleIn     => '',
     BiblioDefaultView        => 'normal',