Refactor API structure and integrate new modular API client

- Replaced legacy apiService with a new modular api client structure.
- Updated AuthContext, OAuthButtons, and AuthCallbackPage to use the new api client.
- Created separate services for auth, sounds, playlists, and users.
- Implemented centralized API configuration and error handling.
- Added support for OAuth providers and token exchange.
- Introduced a Toaster component for notifications in App.
- Updated API endpoints and request handling for better maintainability.

src/lib/api/services/sounds.ts

@@ -0,0 +1,100 @@
+import { apiClient } from '../client'
+import { API_CONFIG } from '../config'
+import type { PaginatedResponse } from '../types'
+
+export interface Sound {
+  id: number
+  title: string
+  description?: string
+  file_url: string
+  duration: number
+  file_size: number
+  mime_type: string
+  play_count: number
+  user_id: number
+  created_at: string
+  updated_at: string
+}
+
+export interface CreateSoundRequest {
+  title: string
+  description?: string
+  file: File
+}
+
+export interface UpdateSoundRequest {
+  title?: string
+  description?: string
+}
+
+export interface SoundsListParams {
+  page?: number
+  size?: number
+  search?: string
+  user_id?: number
+}
+
+export class SoundsService {
+  /**
+   * Get list of sounds with pagination
+   */
+  async list(params?: SoundsListParams): Promise<PaginatedResponse<Sound>> {
+    return apiClient.get<PaginatedResponse<Sound>>(API_CONFIG.ENDPOINTS.SOUNDS.LIST, { 
+      params: params as Record<string, string | number | boolean | undefined>
+    })
+  }
+
+  /**
+   * Get a specific sound by ID
+   */
+  async get(id: string | number): Promise<Sound> {
+    return apiClient.get<Sound>(API_CONFIG.ENDPOINTS.SOUNDS.GET(id))
+  }
+
+  /**
+   * Create a new sound
+   */
+  async create(data: CreateSoundRequest): Promise<Sound> {
+    const formData = new FormData()
+    formData.append('title', data.title)
+    if (data.description) {
+      formData.append('description', data.description)
+    }
+    formData.append('file', data.file)
+
+    return apiClient.post<Sound>(API_CONFIG.ENDPOINTS.SOUNDS.CREATE, formData)
+  }
+
+  /**
+   * Update an existing sound
+   */
+  async update(id: string | number, data: UpdateSoundRequest): Promise<Sound> {
+    return apiClient.patch<Sound>(API_CONFIG.ENDPOINTS.SOUNDS.UPDATE(id), data)
+  }
+
+  /**
+   * Delete a sound
+   */
+  async delete(id: string | number): Promise<void> {
+    return apiClient.delete<void>(API_CONFIG.ENDPOINTS.SOUNDS.DELETE(id))
+  }
+
+  /**
+   * Upload a sound file
+   */
+  async upload(file: File, metadata?: { title?: string; description?: string }): Promise<Sound> {
+    const formData = new FormData()
+    formData.append('file', file)
+    
+    if (metadata?.title) {
+      formData.append('title', metadata.title)
+    }
+    if (metadata?.description) {
+      formData.append('description', metadata.description)
+    }
+
+    return apiClient.post<Sound>(API_CONFIG.ENDPOINTS.SOUNDS.UPLOAD, formData)
+  }
+}
+
+export const soundsService = new SoundsService()