added migration seeders models and test script

app/Models/RecurringTaskCategoryModel.php

@@ -0,0 +1,57 @@
+<?php
+
+namespace App\Models;
+
+use CodeIgniter\Model;
+
+class RecurringTaskCategoryModel extends Model
+{
+    protected $table = 'recurring_task_categories';
+    protected $primaryKey = 'recurring_task_id'; // Composite primary key
+    protected $useAutoIncrement = false;
+    protected $returnType = 'array';
+    protected $useSoftDeletes = false;
+    protected $allowedFields = [
+        'recurring_task_id',
+        'category_id',
+    ];
+
+    protected $useTimestamps = false;
+
+    // Add category to recurring task
+    public function addCategoryToTask($taskId, $categoryId)
+    {
+        return $this->insert([
+            'recurring_task_id' => $taskId,
+            'category_id' => $categoryId,
+        ]);
+    }
+
+    // Remove category from recurring task
+    public function removeCategoryFromTask($taskId, $categoryId)
+    {
+        return $this->where('recurring_task_id', $taskId)
+                    ->where('category_id', $categoryId)
+                    ->delete();
+    }
+
+    // Get categories for a recurring task
+    public function getCategoriesForTask($taskId)
+    {
+        return $this->select('categories.*')
+                    ->join('categories', 'recurring_task_categories.category_id = categories.id')
+                    ->where('recurring_task_categories.recurring_task_id', $taskId)
+                    ->get()
+                    ->getResultArray();
+    }
+
+    // Get recurring tasks for a category
+    public function getTasksForCategory($categoryId)
+    {
+        return $this->select('recurring_tasks.*')
+                    ->join('recurring_tasks', 'recurring_task_categories.recurring_task_id = recurring_tasks.id')
+                    ->where('recurring_task_categories.category_id', $categoryId)
+                    ->get()
+                    ->getResultArray();
+    }
+}