Add WebP/AVIF support detection and serve appropriate image formats

[nanaf6203-bit]

Problem

All users get the same image format regardless of browser capabilities. WebP can reduce image sizes by 25-35%.

Expected Outcome

Images served in best supported format based on Accept header.

Acceptance Criteria

• WebP variant for all uploaded images
• Content negotiation via Accept header
• Vary: Accept header on image responses
• Fallback to original format

Files Affected

src/properties/property-images.service.ts, src/cache/cache-headers.interceptor.ts

Difficulty

Easy

Estimated Effort

Small (2-3 days)

Labels

performance, images, enhancement

[Thommyy7]

@Thommyy7 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Hi, I'd like to work on this issue.

I've worked on blockchain and Web3 projects, including Stellar and Soroban smart contracts, alongside traditional full-stack web development. I'm comfortable moving between frontend, backend, and on-chain work.

I understand what's being asked here and I'm confident I can implement this correctly and efficiently.

Please assign this issue to me, I'd be happy to contribute.

ℹ️ Repo Maintainers: To accept this application, review their application or assign @Thommyy7 to this issue.

[drips-wave]

Congratulations, @Thommyy7! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on July 30, 2026.

🧑‍💻 @Thommyy7: 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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🌊 Happy Wave 🌊

[drips-wave]

This issue has been completed by @Thommyy7 as part of the Stellar Wave Program's 7th Wave 🥳

😎 @Thommyy7: You earned 200 Points for completing this issue! After the current Wave ends, you'll be eligible for a percentage of the Wave's reward pool based on the percentage of total points you've earned. Learn more here. You can also Leave a review to share your experience working on this issue.

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