fix: enable component search and pricing in offline mode

**Problem:**
Configurator was broken in offline mode - no component search
and no price calculation because /api/components returned empty list.

**Solution:**
Added local component fallback to ComponentHandler:

1. **ComponentHandler with localDB** (component.go)
   - Added localDB parameter to NewComponentHandler
   - List() now fallbacks to local_components when offline
   - Converts LocalComponent to ComponentView format
   - Preserves prices from local cache

2. **Updated initialization** (main.go)
   - Pass localDB to NewComponentHandler

**Impact:**
- ✅ Component search works offline
- ✅ Prices load from local_components table
- ✅ Configuration creation fully functional offline
- ✅ Price calculation works with cached prices

**Testing:**
- Verified /api/components returns local components
- Verified current_price field populated from cache
- Search, filtering, and pagination work correctly

Fixes critical Phase 2.5 offline mode issue.

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

internal/handlers/component.go

@@ -5,16 +5,21 @@ import (
 	"strconv"
 
 	"github.com/gin-gonic/gin"
+	"git.mchus.pro/mchus/quoteforge/internal/localdb"
 	"git.mchus.pro/mchus/quoteforge/internal/repository"
 	"git.mchus.pro/mchus/quoteforge/internal/services"
 )
 
 type ComponentHandler struct {
 	componentService *services.ComponentService
+	localDB          *localdb.LocalDB
 }
 
-func NewComponentHandler(componentService *services.ComponentService) *ComponentHandler {
-	return &ComponentHandler{componentService: componentService}
+func NewComponentHandler(componentService *services.ComponentService, localDB *localdb.LocalDB) *ComponentHandler {
+	return &ComponentHandler{
+		componentService: componentService,
+		localDB:          localDB,
+	}
 }
 
 func (h *ComponentHandler) List(c *gin.Context) {
@@ -34,6 +39,40 @@ func (h *ComponentHandler) List(c *gin.Context) {
 		return
 	}
 
+	// If offline mode (empty result), fallback to local components
+	if result.Total == 0 && h.localDB != nil {
+		localFilter := localdb.ComponentFilter{
+			Category: filter.Category,
+			Search:   filter.Search,
+			HasPrice: filter.HasPrice,
+		}
+
+		offset := (page - 1) * perPage
+		localComps, total, err := h.localDB.ListComponents(localFilter, offset, perPage)
+		if err == nil && len(localComps) > 0 {
+			// Convert local components to ComponentView format
+			components := make([]services.ComponentView, len(localComps))
+			for i, lc := range localComps {
+				components[i] = services.ComponentView{
+					LotName:      lc.LotName,
+					Description:  lc.LotDescription,
+					Category:     lc.Category,
+					CategoryName: lc.Category, // No translation in local mode
+					Model:        lc.Model,
+					CurrentPrice: lc.CurrentPrice,
+				}
+			}
+
+			c.JSON(http.StatusOK, &services.ComponentListResult{
+				Components: components,
+				Total:      total,
+				Page:       page,
+				PerPage:    perPage,
+			})
+			return
+		}
+	}
+
 	c.JSON(http.StatusOK, result)
 }