FE-179 Add ESLint rule to ban direct img tag usage in favour of AppImage

[BigBen-7]

Track
Frontend

Difficulty
Trivial

Description
Raw <img> tags bypass Next.js image optimisation. Add a custom ESLint rule (or use @next/next/no-img-element) to ban them and enforce AppImage usage.

Acceptance Criteria

• ESLint config includes @next/next/no-img-element as an error.
• Existing violations are fixed as part of this issue.
• CI lint step fails on any new raw <img> usage.

[Anadudev]

@Anadudev has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

I would love to work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Anadudev to this issue.

[Qoder-Undefined]

@Qoder-Undefined has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainer can I work on this

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Qoder-Undefined to this issue.

[drips-wave]

Congratulations, @Qoder-Undefined! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @Qoder-Undefined: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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