🏷️ Fix duplicate short names for foods

Update the short name calculation logic to account for foods throughout the entire day, not just within individual meals. This ensures that short names remain unique across all meals in a day, preventing duplicate short names that could cause confusion.

The short name calculation currently only ensures uniqueness within a single meal. If the same food appears in multiple meals throughout the day, it may receive the same short name in different meals, which can lead to ambiguity.

Short names should be calculated by considering all foods across all meals in the day. When a food appears multiple times throughout the day (across different meals), the short name algorithm should generate unique identifiers that distinguish between these instances.

• ●This affects the short name generation algorithm used for food items in meal displays
• ●Need to modify the scope of uniqueness checking from meal-level to day-level
• ●Consider performance implications when checking uniqueness across larger datasets (all foods in a day vs. foods in a single meal)
• ●Ensure the changes maintain backward compatibility with existing short name display logic

• ● Short name calculation considers all foods across all meals in the day
• ● No duplicate short names exist for different food items within the same day
• ● Short names remain concise and readable while maintaining uniqueness
• ● Performance remains acceptable even for days with many meals/foods
• ● Existing tests are updated to reflect day-level uniqueness requirements
• ● New tests added to verify cross-meal uniqueness

Extracted from PXL-705

Build instruction: Use -destination 'platform=iOS Simulator,name=iPhone 17 Pro' when building this project