Refactor various modules for clarity, type safety, and documentation

[kbtale]

Summary

Refactor core logic modules and state management to eliminate cryptic variable names, replace magic numbers with derived constants, make bitwise operations self-documenting, and unify storage key conventions across the application.

Changes included:

• Chronometry: Clarified Conway algorithm variables (a, b, c, anchor, diff) and added WeekdayIndex type.
• Storage Units: Migrated from stringified indices to type-safe StorageUnitSymbol and added convertStorageBySymbol.
• Color Theory: Replaced magic number 442 with MAX_RGB_COLOR_DISTANCE constant and added calculateColorScore helper.
• Subnetting: Made 32-bit unsigned bitwise math explicit with toUint32 and exported ipToUint32 / uint32ToIp.
• Luhn Algorithm: Improved loop variable clarity (processedDigit, checksumTotal, shouldDoubleCurrentDigit) and extracted digit doubling helper.
• Storage Service: Unified storage keys under polymath_ prefixes with legacy key fallback and typed date format events.

Type of Change

• Bug fix
• New feature
• Refactoring
• Performance improvement
• Accessibility improvement
• Documentation update

Checklist

• npm run check passes (Biome lint & format)
• npm run test passes (all unit tests)
• npm run build passes (TypeScript strict mode)
• New i18n keys added to all 3 locales (en, es, it)
• No inline styles added (use SCSS modules)