🔗 Add unique pleb+year constraint to payment_events and ensure migration handles duplicates

- 🧹 Prune duplicate `payment_events` before adding the unique index in migration
- ✅ Add tests to verify invoice management, expiration handling, and payment status updates
- ⚙️ Refactor invoice management flow with `resolveCurrentPaymentEvent` and status syncing logic
- 🎨 Enhance UI for invoice status with dynamic messages, labels, and expiration info

database/migrations/2026_01_31_085840_add_unique_pleb_year_index_to_payment_events_table.php

@@ -0,0 +1,52 @@
+<?php
+
+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
+{
+    /**
+     * Run the migrations.
+     */
+    public function up(): void
+    {
+        DB::table('payment_events')
+            ->select('einundzwanzig_pleb_id', 'year', DB::raw('count(*) as total'))
+            ->groupBy('einundzwanzig_pleb_id', 'year')
+            ->havingRaw('count(*) > 1')
+            ->get()
+            ->each(function ($groupedPaymentEvent): void {
+                $idsToKeep = DB::table('payment_events')
+                    ->where('einundzwanzig_pleb_id', $groupedPaymentEvent->einundzwanzig_pleb_id)
+                    ->where('year', $groupedPaymentEvent->year)
+                    ->orderByDesc('paid')
+                    ->orderByDesc('updated_at')
+                    ->pluck('id')
+                    ->toArray();
+
+                $keep = array_shift($idsToKeep);
+
+                if (! empty($idsToKeep)) {
+                    DB::table('payment_events')
+                        ->whereIn('id', $idsToKeep)
+                        ->delete();
+                }
+            });
+
+        Schema::table('payment_events', function (Blueprint $table): void {
+            $table->unique(['einundzwanzig_pleb_id', 'year'], 'payment_events_pleb_year_unique');
+        });
+    }
+
+    /**
+     * Reverse the migrations.
+     */
+    public function down(): void
+    {
+        Schema::table('payment_events', function (Blueprint $table): void {
+            $table->dropUnique('payment_events_pleb_year_unique');
+        });
+    }
+};