Remove recipe name field; use product title internally

The recipe name input is dropped from the product form — the version
number alone identifies a recipe. The product title is stored as the
internal name to satisfy the NOT NULL constraint. The history table
no longer shows the name column.

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

app/Filament/User/Resources/ProductResource.php

@@ -54,12 +54,6 @@ class ProductResource extends Resource {
                     ->columnSpanFull(),
                 Forms\Components\Section::make('Rezept')
                     ->schema([
-                        TextInput::make('recipe_name')
-                            ->label('Name')
-                            ->required()
-                            ->dehydrated(false)
-                            ->afterStateHydrated(fn ($component, $record) =>
-                                $component->state($record?->recipe?->name ?? '')),
                         Placeholder::make('recipe_version')
                             ->label('Version')
                             ->content(fn ($record) => $record?->recipe