29467 Reduce unnecessary re-renders with useCallback

[carolinepaulic]

Description

This is a subtask of https://github.com/allenai/scholar/issues/28926, originally split out from the state management work in https://github.com/allenai/scholar/issues/28332 based on the following feedback:

• https://github.com/allenai/pdf-component-library/pull/17#discussion_r679384569
• https://github.com/allenai/pdf-component-library/pull/17#discussion_r679378238
• https://github.com/allenai/pdf-component-library/pull/17#discussion_r683670343

This PR aims to reduce unnecessary re-renders by wrapping functions that use hooks with useCallback.

Reviewer Instructions

Let me know if you see any places I missed or any functions that I wrapped in a callback where it wasn't needed. There are a couple places in BoundingBox and HighlightOverlay that I will add callbacks to once computeStyleWithContext is refactored (another subtask in the loose ends ticket).

Testing Plan

• Existing functionality works as expected: zoom in/out, rotate CW/CCW, outline (open, scroll to page, close), highlight overlay demo, text highlight demo, scroll to demo
• Run all unit tests locally