[Smart Contract] Pre-flight simulations via Tenderly for every wallet transaction

[nanaf6203-bit]

Problem Statement

Today, every wallet-driven transaction in TransactionConfirmation.tsx, batchTransaction.ts, and secureTransactionUtils.ts is sent to the chain without a pre-flight simulation. Users learn about a failed transaction only after spending gas.

Acceptance Criteria

• New simulateTransaction(txRequest) API wraps viem's estimateContractGas and a Tenderly-style simulateApi.tx call
• Surfaced in the UI as an expandable "Simulated result" section
• Show top-3 expected state changes (token balance deltas, NFT ownership diffs)
• Optional opt-out ("Skip simulation for low-value tx")

Implementation Notes

Tenderly API key kept server-side. Front-end posts via /api/simulate. Vitest fetch mocks emulate Tenderly responses.

Files Likely Affected

• src/utils/tenderlySimulation.ts (new)
• src/app/api/simulate/route.ts (new)
• src/components/TransactionConfirmation.tsx
• src/lib/batchTransaction.ts

Difficulty / Effort

• Difficulty: Hard
• Effort: T-Shirt XL

Labels

web3, priority:high, feature, area:smart-contract

[baling-1]

@baling-1 has applied to work on this issue as part of the Stellar Wave Program's 7th wave.

Gm team, i will like to work on this, i am a smart contract developer with experience skill solving issues like this. i am also an active Open source contributor.
ETA: 4 hours

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[ustaxs]

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

Good day

I have read the requirements of this issue and i am confident that i can solve this

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[drips-wave]

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

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