Optimize affiliate system and add locale-aware defaults

- Show BOM button for unsaved loads (no longer requires save first)
- Set US fallback affiliate tag for unknown countries
- Localize Amazon search queries in all 5 languages (EN/DE/ES/FR/NL)
- Add affiliate URL/country fields to SavedBattery model
- Auto-detect unit system (imperial for US locale, metric otherwise)
- Set charger input voltage based on locale (120V US, 230V EU)
- Remove StoreKitManager and CableProPaywallView
- Add CLAUDE.md project instructions

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Cable/Chargers/ChargerConfiguration.swift

@@ -15,7 +15,7 @@ struct ChargerConfiguration: Identifiable, Hashable {
     init(
         id: UUID = UUID(),
         name: String,
-        inputVoltage: Double = 230.0,
+        inputVoltage: Double = LocaleDefaults.mainsVoltage,
         outputVoltage: Double = 14.2,
         maxCurrentAmps: Double = 30.0,
         maxPowerWatts: Double = 0.0,