Docs: Clarify useEffect non-primitive dependency pitfall

[SaifUrRehman2k]

Docs: Clarify useEffect() non-primitive dependency pitfall

Closes: #8156

Description:

This PR addresses issue #8156 by clarifying the behavior of the useEffect() dependency array when non-primitive values (objects or arrays) are used.

Problem:

The existing documentation doesn't explicitly warn developers about the common pitfall where non-primitive dependencies, which create a new reference on every render, can cause the effect to run on every render (or cause infinite loops)

Solution:

Added a section Behavior of useEffect() with non-primitive dependencies, which includes:

• An explanation of why objects/arrays cause dependency changes on each render.
• Examples demonstrating the issue
• Recommended solutions, such as using useMemo() or defining constant values outside the component

[github-actions]

Size changes

📦 Next.js Bundle Analysis for react-dev

This analysis was generated by the Next.js Bundle Analysis action. 🤖

Five Pages Changed Size

The following pages changed size from the code in this PR compared to its base branch:

Page	Size (compressed)	First Load
/404	127.9 KB (-1 B)	238.44 KB
/500	127.91 KB (-1 B)	238.45 KB
/[[...markdownPath]]	130.34 KB (-1 B)	240.88 KB
/errors	128.15 KB (-1 B)	238.69 KB
/errors/[errorCode]	128.13 KB (-1 B)	238.67 KB

Details

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