Fixes topic tree not showing

[akolson]

Summary

Description of the change(s) you made

This pr fixes a bug in the topics topics side panel where the topic tree is no longer being folded out. It also fixes a minor bug when select all is applied to a paginated list: the number of resources selected should reflect the number of resources currently displayed

Manual verification steps performed

1. Select a channel
2. Navigate around its resources using the side panel

Screenshots (if applicable)

Topic tree

Screen.Recording.2024-09-26.at.13.58.00.mov

Resource count

Screen.Recording.2024-09-26.at.14.07.36.mov

Does this introduce any tech-debt items?

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Reviewer guidance

See manual verification steps above

Are there any risky areas that deserve extra testing?

• Test the pagination workflow as the fix made some enhancements to the pagination implementation

References

Fixes #4756

Comments

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Contributor's Checklist

PR process:

• If this is an important user-facing change, PR or related issue the CHANGELOG label been added to this PR. Note: items with this label will be added to the CHANGELOG at a later time
• If this includes an internal dependency change, a link to the diff is provided
• The docs label has been added if this introduces a change that needs to be updated in the user docs?
• If any Python requirements have changed, the updated requirements.txt files also included in this PR
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Studio-specifc:

• All user-facing strings are translated properly
• The notranslate class been added to elements that shouldn't be translated by Google Chrome's automatic translation feature (e.g. icons, user-generated text)
• All UI components are LTR and RTL compliant
• Views are organized into pages, components, and layouts directories as described in the docs
• Users' storage used is recalculated properly on any changes to main tree files
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Testing:

• Code is clean and well-commented
• Contributor has fully tested the PR manually
• If there are any front-end changes, before/after screenshots are included
• Critical user journeys are covered by Gherkin stories
• Any new interactions have been added to the QA Sheet
• Critical and brittle code paths are covered by unit tests

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Reviewer's Checklist

This section is for reviewers to fill out.

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[marcellamaki]

I reviewed #4741 for context, and based on those changes, and the slack discussion, the updates here make sense to me for code review. I also checked manual QA for both the topic tree in the sidebar and pagination, and both seem to be working as expected. Thanks, Samson!

[pcenov]

LGTM as well!