fix(create-next-app): make AGENTS.md blue (#95432)
I noticed that this last question for AGENTS.md doesn't have any blue
highlighted word.
So I made AGENTS.md blue to follow the convention of the others.
<img width="865" height="163" alt="image"
src="https://github.com/user-attachments/assets/d10f74e1-f5ec-4c8a-9c6d-8d01b9c1abf3"
/>
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Co-authored-by: Joseph <joseph.chamochumbi@vercel.com>
