feat: handle duplicate children in container pages [FC-0112]

[navinkarkera]

Description

If we have duplicate container or component in parent page in library, clicking on one of them selects both and removing any one from the parent blocks removes all instances.
This PR handles duplicates by including index/order_number of each child component in the url and using it to exclude a single instance and update parent structure.

Useful information to include:

• Which user roles will this change impact? "Course Author"

Supporting information

• Selection behavior for duplicate component #2454
• Private-ref: https://tasks.opencraft.com/browse/FAL-4270

Testing instructions

• Add same child item under any unit/subsection/section
• Verify that you can select one element and remove it while maintaining the correct order.

Other information

Include anything else that will help reviewers and consumers understand the change.

• Does this change depend on other changes elsewhere?
• Any special concerns or limitations? For example: deprecations, migrations, security, or accessibility.

Best Practices Checklist

We're trying to move away from some deprecated patterns in this codebase. Please
check if your PR meets these recommendations before asking for a review:

• Any new files are using TypeScript (.ts, .tsx).
• Deprecated propTypes, defaultProps, and injectIntl patterns are not used in any new or modified code.
• Tests should use the helpers in src/testUtils.tsx (specifically initializeMocks)
• Do not add new fields to the Redux state/store. Use React Context to share state among multiple components.
• Use React Query to load data from REST APIs. See any apiHooks.ts in this repo for examples.
• All new i18n messages in messages.ts files have a description for translators to use.
• Imports avoid using ../. To import from parent folders, use @src, e.g. import { initializeMocks } from '@src/testUtils'; instead of from '../../../../testUtils'

[openedx-webhooks]

Thanks for the pull request, @navinkarkera!

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[codecov]

Codecov Report

❌ Patch coverage is 98.13084% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 94.81%. Comparing base (36c9eba) to head (5d929ae).
⚠️ Report is 2 commits behind head on master.

Files with missing lines	Patch %	Lines
.../library-authoring/components/ComponentRemover.tsx	96.42%	1 Missing ⚠️
src/library-authoring/data/apiHooks.ts	91.66%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##           master    #2584    +/-   ##
========================================
  Coverage   94.81%   94.81%            
========================================
  Files        1225     1225            
  Lines       27481    27514    +33     
  Branches     6187     6037   -150     
========================================
+ Hits        26056    26088    +32     
- Misses       1367     1368     +1     
  Partials       58       58            

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[bradenmacdonald]

Suggested change

	afterEach(() => {
	jest.clearAllMocks();
	axiosMock.restore();
	});

This is not necessary - initializeMocks() already calls clearAllMocks() for you, and it re-creates the axiosMock each time.

[bradenmacdonald]

Instead of T can you call this ChildType or something more obvious, and make it default to LibraryBlockMetadata[] | Container[] ?

Suggested change

	export async function getLibraryContainerChildren<T>(
	export async function getLibraryContainerChildren<ChildType = LibraryBlockMetadata | Container>(

Same with useContainerChildren - just looking at the hook it's not obvious what the T type parameter is for, and it should have a sensible default type.

[navinkarkera]

That looks better. Thanks!

[rpenido]

LGTM 👍
Thank you for your work, @navinkarkera!

• I tested this using the instructions from the PR
• I read through the code
• I checked for accessibility issues
• Includes documentation

[ChrisChV]

@navinkarkera Looks good! I commented on some nits

[navinkarkera]

@ChrisChV This is ready to be merged.