082: Contract Error Parsing and UI Display

[bakarezainab]

#082: Contract Error Parsing and UI Display

Category: [FRONTEND]
Difficulty: ● MEDIUM
Tags: error-handling, soroban, xdr, ux, contract

Description

Implement a dedicated contract error parser that decodes Soroban invocation failures from XDR result codes into human-readable messages, matching the pattern established in transactionSimulation.ts. Render these structured errors in a collapsible error panel on any page that invokes a Soroban contract, replacing generic "Transaction Failed" toasts.

Acceptance Criteria

• parseContractError(resultXdr) utility function decodes known contract error codes.
• Error panel component shows error code, human-readable description, and suggested action.
• Panel used consistently across PayrollScheduler, CrossAssetPayment, and vesting UI.
• Unknown error codes fall back to raw XDR display with a copy button.
• Integration tests cover all mapped error codes.