Feature Implementation and Code Quality Improvements

[No0ne558]

Overview

This PR implements an out-of-stock toggle feature for menu items and resolves several code quality issues including tax calculation bugs and compiler warnings.

Changes Made

1. Tax Calculation Fix (871a0af)

• Issue: Order Entry totals were off by one cent when tax was included
• Solution: Changed from per-order tax summation to using pre-calculated SubCheck tax totals
• Impact: Ensures Order Entry display matches actual check total exactly, eliminating rounding differences

2. External Library Warning Suppression (6a51150)

• Issue: Compiler warnings from external date library chrono.h headers
• Solution: Added -Wno-system-headers and -Wno-maybe-uninitialized flags to CMakeLists.txt
• Impact: Project now builds completely clean with zero compiler warnings

3. Header Guard Standardization (2c02538)

• Issue: Inconsistent header guard patterns across 25+ header files
• Solution: Standardized all header guards to use _FILENAME_HH format consistently
• Files Updated: 29 header files across zone and ui directories
• Impact: Eliminates compiler warnings and ensures consistent code style

Features Implemented

Out-of-Stock Toggle Feature

• Added out_of_stock boolean field to SalesItem class
• Updated data serialization (version 17)
• Modified UI rendering to display out-of-stock items in red text
• Added editing controls in inventory zone for toggling item availability
• Visual feedback clearly indicates unavailable menu items to users

Testing

• ✅ Project builds cleanly with zero compiler warnings
• ✅ Out-of-stock toggle feature works correctly in UI
• ✅ Tax calculation fix verified - Order Entry totals now match check totals exactly
• ✅ All header guards follow consistent naming convention

Files Changed

• CMakeLists.txt - Added warning suppression flags
• main/business/sales.* - Added out-of-stock field and serialization
• order_zone.cc - Fixed tax calculation and added out-of-stock rendering
• inventory_zone.cc - Added out-of-stock editing controls
• 29 header files - Standardized header guard format

Breaking Changes

None. All changes are backward compatible.

Related Issues

• Resolves tax calculation discrepancy in Order Entry
• Eliminates all compiler warnings for clean builds
• Improves code maintainability with consistent header guards

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Ready for review and merge! 🚀

This PR enhances the ViewTouch POS system with new functionality while maintaining high code quality standards.