chore: Phase 1 Code Quality & Static Sweep

[VrtxOmega]

Implemented Phase 1: setup ESLint/Prettier with a lint script and auto-fixed standard formatting and unused vars issues. Extracted hardcoded fallbacks in QR Scanner and WS services to a structured env.js config file. Finally, modified bare catch blocks in SettingsScreen and ApprovalModal to securely log stacktraces. Included fix for android/gradlew permissions.

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PR created automatically by Jules for task 17107034632588646712 started by @VrtxOmega

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