chore: bootstrap module from working instance and add install guide

models/DonationBlock.php

@@ -0,0 +1,46 @@
+<?php
+
+namespace humhub\modules\donations\models;
+
+use humhub\components\ActiveRecord;
+
+class DonationBlock extends ActiveRecord
+{
+    public static function tableName()
+    {
+        return 'rescue_donation_block';
+    }
+
+    public function rules()
+    {
+        return [
+            [['contentcontainer_id', 'placement'], 'required'],
+            [['contentcontainer_id', 'goal_id', 'is_active', 'sort_order'], 'integer'],
+            [['placement'], 'string', 'max' => 64],
+            [['header'], 'string', 'max' => 190],
+        ];
+    }
+
+    public function beforeSave($insert)
+    {
+        if (!parent::beforeSave($insert)) {
+            return false;
+        }
+
+        $now = date('Y-m-d H:i:s');
+        if ($insert && empty($this->created_at)) {
+            $this->created_at = $now;
+        }
+        $this->updated_at = $now;
+
+        if ($this->sort_order === null) {
+            $this->sort_order = 100;
+        }
+
+        if ($this->is_active === null) {
+            $this->is_active = 1;
+        }
+
+        return true;
+    }
+}