feat: Auto-collapse sidebar sub-navigation when opening a new section

[TarunyaProgrammer]

What kind of change does this PR introduce?

• Bug fix (UI / UX behavior)

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Issue Number:

• Closes 🐛 Bug: Sidebar sub-navigation does not auto-collapse #2197

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Screenshots/videos:

JsonSchema2.mov

Attached screen recording demonstrating the updated accordion behavior where opening a sidebar section automatically collapses the previously opened one.

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If relevant, did you update the documentation?

Not required.
This change only affects client-side navigation behavior and does not modify documentation content.

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Summary

The documentation sidebar currently allows multiple sub-navigation sections to remain expanded simultaneously, which leads to visual clutter and makes navigation harder to scan.

This PR updates the sidebar interaction to behave as a mutually exclusive accordion:

• When a new sidebar section is expanded, any previously expanded section is automatically collapsed.
• Only one sub-navigation section can be open at a time.

The change improves usability and accessibility while preserving existing markup, animations, and data attributes. No data models, APIs, or content were modified.

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Does this PR introduce a breaking change?

No.
This is a non-breaking, client-side UI behavior change that does not affect existing routes, data, or public APIs.

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Checklist

• Read, understood, and followed the contributing guidelines.