Stage 4 — Labor Catalog: fixed price + default parts + service templates

Schema:
- labors.pricing_mode (hourly/fixed) + fixed_price
- labor_parts (default parts auto-added with a labor)
- service_templates + service_template_items (labor/part bundles)

ServiceComposer:
- addLabor(wo, labor, withParts) — hourly (hours×rate) or fixed (fixed_price),
  then auto-adds the labor's default parts
- addPart(wo, part, qty) — catalog price snapshot
- applyTemplate(wo, template) — adds all labor+part lines, recalcs total
- hourlyRate from settings.labor_rate

Filament:
- LaborResource: pricing_mode (live) toggles hours/fixed_price fields,
  DefaultPartsRelationManager
- ServiceTemplateResource (Service group) with ItemsRelationManager
- WorkOrder edit "Aplică șablon" action → applyTemplate
- WorksRelationManager CreateAction auto-adds labor default parts

Tests (6 new):
- hourly rate×hours; fixed uses fixed_price; default parts auto-added;
  withParts=false skips; applyTemplate adds lines + recalcs total;
  templates tenant-isolated

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

app/Models/Tenant/Labor.php

@@ -4,6 +4,7 @@ namespace App\Models\Tenant;
 
 use App\Models\Concerns\BelongsToTenant;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Database\Eloquent\SoftDeletes;
 
 class Labor extends Model
@@ -15,14 +16,34 @@ class Labor extends Model
         'Caroserie', 'Electrică', 'Climatizare', 'Eșapament', 'Altele',
     ];
 
+    public const PRICING_MODES = [
+        'hourly' => 'Pe oră (normă × tarif)',
+        'fixed' => 'Preț fix',
+    ];
+
     protected $fillable = [
         'company_id', 'category', 'name_ro', 'name_ru', 'code',
-        'hours', 'price', 'is_active', 'notes',
+        'hours', 'pricing_mode', 'fixed_price', 'price', 'is_active', 'notes',
     ];
 
     protected $casts = [
         'hours' => 'decimal:2',
+        'fixed_price' => 'decimal:2',
         'price' => 'decimal:2',
         'is_active' => 'boolean',
     ];
+
+    public function laborParts(): HasMany
+    {
+        return $this->hasMany(LaborPart::class);
+    }
+
+    /** Effective line total for this labor given the tenant hourly rate. */
+    public function effectiveTotal(float $hourlyRate): float
+    {
+        if ($this->pricing_mode === 'fixed') {
+            return (float) $this->fixed_price;
+        }
+        return round((float) $this->hours * $hourlyRate, 2);
+    }
 }