- main.js: global error handlers (error + unhandledrejection), try/catch around App mount with inline fallback UI
- bindings_logging.go: FrontendLog() and LogStartupStep() backend bindings for persistent application logging
- App.js: FrontendLog() and LogStartupStep() Wails JS bindings
- docs/frontend-architecture.md: component architecture, state ownership rules, communication patterns, logging guide, troubleshooting
All existing code untouched. This is a pure additive step that enables
blank-window debugging before any App.svelte extraction begins.