feat: add related todos functionality in task editing

- Implemented `RelatedTodos` component in `EditTaskForm` to display and manage related todos for a task.
- Updated `TasksClient` to fetch daily checkboxes related to a task.
- Enhanced `TasksService` with a method to retrieve related daily checkboxes from the database.
- Added functionality to create new todos linked to tasks in the daily actions.
- Marked the task for displaying related todos in the task editing interface as complete in TODO.md.

src/actions/daily.ts

@@ -1,7 +1,7 @@
 'use server';
 
 import { dailyService } from '@/services/daily';
-import { UpdateDailyCheckboxData, DailyCheckbox } from '@/lib/types';
+import { UpdateDailyCheckboxData, DailyCheckbox, CreateDailyCheckboxData } from '@/lib/types';
 import { revalidatePath } from 'next/cache';
 
 /**
@@ -198,6 +198,40 @@ export async function deleteCheckbox(checkboxId: string): Promise<{
   }
 }
 
+/**
+ * Ajoute un todo lié à une tâche
+ */
+export async function addTodoToTask(taskId: string, text: string, date?: Date): Promise<{
+  success: boolean;
+  data?: DailyCheckbox;
+  error?: string;
+}> {
+  try {
+    const targetDate = date || new Date();
+    targetDate.setHours(0, 0, 0, 0);
+
+    const checkboxData: CreateDailyCheckboxData = {
+      date: targetDate,
+      text: text.trim(),
+      type: 'task',
+      taskId: taskId,
+      isChecked: false
+    };
+
+    const checkbox = await dailyService.addCheckbox(checkboxData);
+    
+    revalidatePath('/daily');
+    revalidatePath('/kanban');
+    return { success: true, data: checkbox };
+  } catch (error) {
+    console.error('Erreur addTodoToTask:', error);
+    return {
+      success: false,
+      error: error instanceof Error ? error.message : 'Erreur inconnue'
+    };
+  }
+}
+
 /**
  * Réorganise les checkboxes d'une date
  */