refactor: remove CurrentPrice from local_components and transition to pricelist-based pricing

## Overview
Removed the CurrentPrice and SyncedAt fields from local_components, transitioning to a
pricelist-based pricing model where all prices are sourced from local_pricelist_items
based on the configuration's selected pricelist.

## Changes

### Data Model Updates
- **LocalComponent**: Now stores only metadata (LotName, LotDescription, Category, Model)
  - Removed: CurrentPrice, SyncedAt (both redundant)
  - Pricing is now exclusively sourced from local_pricelist_items

- **LocalConfiguration**: Added pricelist selection fields
  - Added: WarehousePricelistID, CompetitorPricelistID
  - These complement the existing PricelistID (Estimate)

### Migrations
- Added migration "drop_component_unused_fields" to remove CurrentPrice and SyncedAt columns
- Added migration "add_warehouse_competitor_pricelists" to add new pricelist fields

### Component Sync
- Removed current_price from MariaDB query
- Removed CurrentPrice assignment in component creation
- SyncComponentPrices now exclusively updates based on pricelist_items via quote calculation

### Quote Calculation
- Added PricelistID field to QuoteRequest
- Updated local-first path to use pricelist_items instead of component.CurrentPrice
- Falls back to latest estimate pricelist if PricelistID not specified
- Maintains offline-first behavior: local queries work without MariaDB

### Configuration Refresh
- Removed fallback on component.CurrentPrice
- Prices are only refreshed from local_pricelist_items
- If price not found in pricelist, original price is preserved

### API Changes
- Removed CurrentPrice from ComponentView
- Components API no longer returns pricing information
- Pricing is accessed via QuoteService or PricelistService

### Code Cleanup
- Removed UpdateComponentPricesFromPricelist() method
- Removed EnsureComponentPricesFromPricelists() method
- Updated UnifiedRepository to remove offline pricing logic
- Updated converters to remove CurrentPrice mapping

## Architecture Impact
- Components = metadata store only
- Prices = managed by pricelist system
- Quote calculation = owns all pricing logic
- Local-first behavior preserved: SQLite queries work offline, no MariaDB dependency

## Testing
- Build successful
- All code compiles without errors
- Ready for migration testing with existing databases

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

internal/services/local_configuration.go

@@ -347,7 +347,7 @@ func (s *LocalConfigurationService) RefreshPrices(uuid string, ownerUsername str
 	}
 	latestPricelist, latestErr := s.localDB.GetLatestLocalPricelist()
 
-	// Update prices for all items
+	// Update prices for all items from pricelist
 	updatedItems := make(localdb.LocalConfigItems, len(localCfg.Items))
 	for i, item := range localCfg.Items {
 		if latestErr == nil && latestPricelist != nil {
@@ -362,20 +362,8 @@ func (s *LocalConfigurationService) RefreshPrices(uuid string, ownerUsername str
 			}
 		}
 
-		// Fallback to current component price from local cache
-		component, err := s.localDB.GetLocalComponent(item.LotName)
-		if err != nil || component.CurrentPrice == nil {
-			// Keep original item if component not found or no price available
-			updatedItems[i] = item
-			continue
-		}
-
-		// Update item with current price from local cache
-		updatedItems[i] = localdb.LocalConfigItem{
-			LotName:   item.LotName,
-			Quantity:  item.Quantity,
-			UnitPrice: *component.CurrentPrice,
-		}
+		// Keep original item if price not found in pricelist
+		updatedItems[i] = item
 	}
 
 	// Update configuration
@@ -672,7 +660,7 @@ func (s *LocalConfigurationService) RefreshPricesNoAuth(uuid string) (*models.Co
 	}
 	latestPricelist, latestErr := s.localDB.GetLatestLocalPricelist()
 
-	// Update prices for all items
+	// Update prices for all items from pricelist
 	updatedItems := make(localdb.LocalConfigItems, len(localCfg.Items))
 	for i, item := range localCfg.Items {
 		if latestErr == nil && latestPricelist != nil {
@@ -687,20 +675,8 @@ func (s *LocalConfigurationService) RefreshPricesNoAuth(uuid string) (*models.Co
 			}
 		}
 
-		// Fallback to current component price from local cache
-		component, err := s.localDB.GetLocalComponent(item.LotName)
-		if err != nil || component.CurrentPrice == nil {
-			// Keep original item if component not found or no price available
-			updatedItems[i] = item
-			continue
-		}
-
-		// Update item with current price from local cache
-		updatedItems[i] = localdb.LocalConfigItem{
-			LotName:   item.LotName,
-			Quantity:  item.Quantity,
-			UnitPrice: *component.CurrentPrice,
-		}
+		// Keep original item if price not found in pricelist
+		updatedItems[i] = item
 	}
 
 	// Update configuration