[Feature]: 2-minute demo video

[luchobonatti]

User story / Problem statement

The bounty requires a demo video as a scoring criterion. Judges need to see all user stories working end-to-end on Sepolia without running the code themselves.

Proposed solution

Record a 2-minute screen capture covering all scenarios in order:

Scenario	Duration	What to show
US-01	20s	Upload CSV → encrypt → batchAddEmployees tx confirmed
US-02	15s	Approve USDC → wrap to payroll → balance updated
US-03	15s	Run Payroll → PayrollExecuted event → 0 amounts in events
US-04	15s	Roster → Reveal salary → plaintext appears in browser
US-05	20s	Employee view → Decrypt Salary → $X,XXX.00 shown
US-06	15s	Check Balance → cUSDC balance decrypted
US-07	20s	Unwrap → Pending → Finalized → USDC in wallet

Key points to highlight:

• Etherscan Sepolia showing encrypted Transfer events (no amounts)
• Browser devtools showing no salary values in network requests
• Verified contract source on Etherscan

Acceptance criteria

• Video is ≤ 2 minutes
• All 7 user stories (US-01 through US-07) demonstrated
• Sepolia network visible in wallet throughout
• Etherscan tx shown for at least one payroll run
• Video uploaded and link added to README
• README updated with: live URL, contract addresses, video link

Technical notes

• Use Loom, OBS, or QuickTime
• Record at 1080p minimum
• Narrate or add captions — judges may watch without audio context

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Part of Epic #15 — Infra