Feat: Add Bulk Import UI for lists

[395ShikharSingh]

Issue Reference

Closes #11672

Summary

This PR implements a new Bulk Import feature that allows users to add multiple books to a list by:

• Entering a URL containing book ISBNs
• Pasting a list of ISBNs directly
• Pasting Open Library Edition IDs

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Files Changed

File	Purpose
openlibrary/plugins/upstream/account.py	Added bulk_import route class for /account/import/bulk
openlibrary/templates/account/import_bulk.html	Template that loads the JS and initializes the UI
static/css/page-import-bulk.less	Styles for the bulk import page
static/bookmarklets/isbn_importer_prototype.js	Main JavaScript containing all the logic

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Function Reference

Core ISBN/Edition Functions

Function	Description
fetchWithProxy(url)	Fetches external URLs through CORS proxies
extractIsbns(text)	Extracts ISBN-10 and ISBN-13 from text using regex
isValidIsbn(isbn)	Validates ISBN checksums
lookupEditions(isbns)	Batch looks up ISBNs via Open Library Search API, returns edition objects with editionKey, title, coverId
importBooksFromUrl(url)	Fetches a URL, extracts ISBNs, and looks them up
importBooksFromIsbns(input)	Parses ISBN text input and looks them up

List Management Functions

Function	Description
getLoggedInUsername()	Detects logged-in user by checking /account redirect or parsing page
fetchUserLists(username)	Fetches user's existing lists from /people/{username}/lists.json
createList(username, name, description)	Creates a new list via POST to /people/{username}/lists
addEditionsToList(listKey, editions)	Adds editions to a list via POST to {listKey}/seeds.json

Orchestration Functions (Console Usage)

Function	Description
importAndAddToList(url, listName)	Imports from URL and creates a new list
importAndAddToExistingList(url, listKey)	Imports from URL and adds to existing list
showMyLists()	Displays user's lists in console table

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Screenshots

Screen.Recording-1.mov

Screen.Recording-2.mov

Note: I couldn’t test this URL feature locally, but I tested it on https://openlibrary.org/, and it worked.

Screen.Recording-3.mov

Stakeholders

@mekarpeles

[accesslint]

There are accessibility issues in these changes.

[accesslint]

👏 You fixed the issue(s)! Great work.