fix(api): resolve dependency conflicts blocking Backend CI and E2E - #247

'prismaService' is assigned a value but never used

'Inject' is defined but never used

'module' is assigned a value but never used

'Optional' is defined but never used

'signature' is defined but never used

'challenge' is defined but never used

'account' is defined but never used

'JwtAuthGuard' is defined but never used

'ApiBearerAuth' is defined but never used

'UseGuards' is defined but never used

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/