feat: migrate tag management to server actions

- Completed migration of tag management to server actions by creating `actions/tags.ts` for CRUD operations.
- Removed obsolete API routes for tags (`/api/tags`, `/api/tags/[id]`) and updated related components to utilize new server actions.
- Updated `TagForm` and `useTags` hook to handle tag creation, updating, and deletion through server actions, improving performance and simplifying client-side logic.
- Cleaned up `tags-client.ts` by removing unused types and methods, focusing on validation only.
- Marked related TODO items as complete in `TODO.md`.

clients/tags-client.ts

@@ -1,17 +1,7 @@
 import { HttpClient } from './base/http-client';
 import { Tag, ApiResponse } from '@/lib/types';
 
-// Types pour les requêtes
-export interface CreateTagData {
-  name: string;
-  color: string;
-}
-
-export interface UpdateTagData {
-  tagId: string;
-  name?: string;
-  color?: string;
-}
+// Types pour les requêtes (now only used for validation - CRUD operations moved to server actions)
 
 export interface TagFilters {
   q?: string; // Recherche par nom
@@ -89,27 +79,7 @@ export class TagsClient extends HttpClient {
     return this.get<TagResponse>(`/${id}`);
   }
 
-  /**
-   * Crée un nouveau tag
-   */
-  async createTag(data: CreateTagData): Promise<TagResponse> {
-    return this.post<TagResponse>('', data);
-  }
-
-  /**
-   * Met à jour un tag
-   */
-  async updateTag(data: UpdateTagData): Promise<TagResponse> {
-    const { tagId, ...updates } = data;
-    return this.patch<TagResponse>(`/${tagId}`, updates);
-  }
-
-  /**
-   * Supprime un tag
-   */
-  async deleteTag(id: string): Promise<ApiResponse<void>> {
-    return this.delete<ApiResponse<void>>(`/${id}`);
-  }
+  // CRUD operations removed - now handled by server actions in /actions/tags.ts
 
   /**
    * Valide le format d'une couleur hexadécimale
@@ -139,9 +109,9 @@ export class TagsClient extends HttpClient {
   }
 
   /**
-   * Valide les données d'un tag
+   * Valide les données d'un tag (utilisé par les formulaires avant server actions)
    */
-  static validateTagData(data: Partial<CreateTagData>): string[] {
+  static validateTagData(data: { name?: string; color?: string }): string[] {
     const errors: string[] = [];
 
     if (!data.name || typeof data.name !== 'string') {