feat: add Work Proof Loop section to landing page

[Kaustubhh-Deshmukh-Git]

Closes #100

Summary

Added a WorkProofLoop landing page section that explains
Gibwork's proof-based submission and payout workflow to new visitors.

Changes

• components/work-proof-loop.tsx — new component with:
  • 4-step proof loop (Choose Work → Submit Proof → Get Reviewed → Get Paid)
  • 3 fallback task cards (category, reward, deadline, proof type)
  • Submission quality checklist
  • Dual CTA row (Explore Funded Work + Create a Task)
• app/page.tsx — imported and inserted <WorkProofLoop />
  between <LogoList /> and <LookingFor />

Verification

• npm run lint ✅ passes
• npm run build ✅ passes
• Mobile: vertical stack layout ✅
• Desktop: horizontal row/grid layout ✅

[vercel]

@Kaustubhh-Deshmukh-Git is attempting to deploy a commit to the gibwork Team on Vercel.

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[Kaustubhh-Deshmukh-Git]

Hi team! Just following up on this PR. Happy to make any
changes if needed. Let me know your thoughts!