- Remove AuthService.cs, Login.razor, Logout.razor (cause build failures)
- Restore MainLayout to original version
- Remove Authentication namespace usings from _Imports.razor
- Clean csproj back to original packages
- Phase 18 (Auth Middleware) moved to pending status in docs
- State.razor: PLC connection state monitor with connect/disconnect controls
- Records.razor: Historical data records viewer with configurable count
- Update NavMenu with proper icon classes
- Update ARCHITECTURE_AND_SPEC.md phase status table
- PlcVanguard.Core: S7.net 0.2.0 PLC driver with MemAddress parser and DataProxy models
- PlcVanguard.Web: Blazor dashboard with live monitoring, counter trendline, and history
- ArchitectureAndSpec.md: complete architecture specification for PlcVanguard system
- Full solution builds with 0 errors and 0 warnings