fix: enable next/image optimization in ProfileCard (#2546)

[aaniya22]

Summary

Removed the unoptimized flag from ProfileCard's avatar <Image> so Next.js can actually optimize it, and allowlisted images.unsplash.com (the fallback avatar source) in next.config.mjs for both image remotePatterns and the CSP img-src directive.

Closes #2546

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Type of Change

• ⚡ Performance improvement

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What Changed

• Removed unoptimized prop from the <Image> component in src/components/ProfileCard.tsx
• Added images.unsplash.com to images.remotePatterns in next.config.mjs
• Added https://images.unsplash.com to the CSP img-src directive in next.config.mjs

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How to Test

1. Render a ProfileCard without passing an avatarUrl prop (so it falls back to the Unsplash placeholder)
2. Confirm the avatar loads correctly and check Network tab — the image should be served through /_next/image rather than the raw Unsplash URL
3. Run npx vitest run test/components/ProfileCard.test.tsx

Expected result: Avatar renders correctly, image requests are optimized via Next.js image pipeline, no CSP violations in console, all 4 existing tests pass.

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Checklist

• Linked the related issue above
• Self-reviewed my own diff
• No unnecessary console.log, debug code, or commented-out blocks
• npm run lint passes locally
• No TypeScript errors (npm run type-check)
• Added or updated tests where applicable
• Updated documentation / comments if behavior changed

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Accessibility (UI changes only)

N/A — no UI/markup change, only image optimization behavior.

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Additional Context

None.

[github-actions]

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