fix: use correct property declaration for withinTransaction

The parent Migration class defines $withinTransaction without a type
hint. Setting it without redeclaring (no "bool" type) avoids the PHP
8.4 error: "Type of Migration::$withinTransaction must not be defined"

This is the proper Laravel way to disable transactions for migrations
that need to run CREATE INDEX CONCURRENTLY in PostgreSQL.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

database/migrations/2025_06_26_131350_optimize_activity_log_indexes.php

@@ -6,28 +6,26 @@
 
 return new class extends Migration
 {
+    /**
+     * Disable transactions for this migration because CREATE INDEX CONCURRENTLY
+     * cannot run inside a transaction block in PostgreSQL.
+     */
+    public $withinTransaction = false;
+
     /**
      * Run the migrations.
      */
     public function up(): void
     {
         try {
-            // CREATE INDEX CONCURRENTLY cannot run inside a transaction block
-            // We need to commit any open transaction first
-            DB::commit();
-
             // Add specific index for type_uuid queries with ordering
             DB::unprepared('CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_activity_type_uuid_created_at ON activity_log ((properties->>\'type_uuid\'), created_at DESC)');
 
             // Add specific index for status queries on properties
             DB::unprepared('CREATE INDEX CONCURRENTLY IF NOT EXISTS idx_activity_properties_status ON activity_log ((properties->>\'status\'))');
 
-            // Begin a new transaction for subsequent migrations
-            DB::beginTransaction();
         } catch (\Exception $e) {
             Log::error('Error adding optimized indexes to activity_log: '.$e->getMessage());
-            // Ensure we have a transaction for subsequent migrations
-            DB::beginTransaction();
         }
     }
 
@@ -37,16 +35,10 @@ public function up(): void
     public function down(): void
     {
         try {
-            // DROP INDEX CONCURRENTLY cannot run inside a transaction block
-            DB::commit();
-
             DB::unprepared('DROP INDEX CONCURRENTLY IF EXISTS idx_activity_type_uuid_created_at');
             DB::unprepared('DROP INDEX CONCURRENTLY IF EXISTS idx_activity_properties_status');
-
-            DB::beginTransaction();
         } catch (\Exception $e) {
             Log::error('Error dropping optimized indexes from activity_log: '.$e->getMessage());
-            DB::beginTransaction();
         }
     }
 };