Restructure batch origins: nested entries per ingredient with Supplier/Farmer selects

Each BatchOrigin (spice) now has multiple BatchOriginEntry rows, replacing the flat
single-supplier/farmer fields. Lieferant and Landwirt are Select fields backed by
dedicated tables with inline create support. Migration preserves existing data.

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

database/migrations/2026_09_12_220000_restructure_batch_origins.php

@@ -0,0 +1,70 @@
+<?php
+
+use App\Models\Farmer;
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('farmers', function (Blueprint $table) {
+            $table->id();
+            $table->string('name');
+            $table->timestamps();
+        });
+
+        Schema::create('batch_origin_entries', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('batch_origin_id')->constrained('batch_origins')->cascadeOnDelete();
+            $table->foreignId('supplier_id')->nullable()->constrained('suppliers')->nullOnDelete();
+            $table->string('origin_country')->nullable();
+            $table->foreignId('farmer_id')->nullable()->constrained('farmers')->nullOnDelete();
+            $table->text('notes')->nullable();
+            $table->timestamps();
+        });
+
+        // Migrate existing batch_origin rows → batch_origin_entries
+        $existing = DB::table('batch_origins')->get();
+        foreach ($existing as $row) {
+            $farmerId = null;
+            if (! empty($row->farmer)) {
+                $farmerId = DB::table('farmers')->insertGetId([
+                    'name'       => $row->farmer,
+                    'created_at' => now(),
+                    'updated_at' => now(),
+                ]);
+            }
+
+            DB::table('batch_origin_entries')->insert([
+                'batch_origin_id' => $row->id,
+                'supplier_id'     => $row->supplier_id,
+                'origin_country'  => $row->origin_country,
+                'farmer_id'       => $farmerId,
+                'notes'           => $row->notes,
+                'created_at'      => now(),
+                'updated_at'      => now(),
+            ]);
+        }
+
+        Schema::table('batch_origins', function (Blueprint $table) {
+            $table->dropForeign(['supplier_id']);
+            $table->dropColumn(['supplier_id', 'origin_country', 'farmer', 'notes']);
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('batch_origins', function (Blueprint $table) {
+            $table->foreignId('supplier_id')->nullable()->constrained('suppliers')->nullOnDelete();
+            $table->string('origin_country')->nullable();
+            $table->string('farmer')->nullable();
+            $table->text('notes')->nullable();
+        });
+
+        Schema::dropIfExists('batch_origin_entries');
+        Schema::dropIfExists('farmers');
+    }
+};