fix: replace mock JWT tokens with real wallet-signature auth (Closes #35) - #67

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4, actions/setup-node@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

'isFailed' is assigned a value but never used

'nextInstallment' is assigned a value but never used

React Hook useCallback has a missing dependency: 't'. Either include it or remove the dependency array

'displayName' is assigned a value but never used

'isLoading' is assigned a value but never used

'reputation' is assigned a value but never used

'formatCurrency' is defined but never used

'isSigning' is assigned a value but never used

'Button' is defined but never used

'setCurrentStep' is assigned a value but never used