refactor(config): 将AI配置逻辑迁移至统一的状态管理store

- 移除独立的ai-config.ts文件，将其功能整合到use-config-store
- 更新所有组件导入路径从 "@/lib/ai-config" 到 "@/stores/use-config-store"
- 实现云端渠道和本地直连两种配置模式的支持
- 添加模型渠道配置管理和API请求代理转发功能
- 统一配置验证逻辑和有效配置获取方法
- 更新组件中使用的配置状态钩子和API调用方式

web/src/lib/ai-config.ts

@@ -1,37 +0,0 @@
-export type AiConfig = {
-  baseUrl: string;
-  apiKey: string;
-  model: string;
-  imageModel: string;
-  textModel: string;
-  systemPrompt: string;
-  models: string[];
-  quality: string;
-  size: string;
-  count: string;
-};
-
-export const CONFIG_STORE_KEY = "infinite-canvas:ai_config_store";
-
-export const defaultConfig: AiConfig = {
-  baseUrl: "https://api.openai.com",
-  apiKey: "",
-  model: "gpt-image-2",
-  imageModel: "gpt-image-2",
-  textModel: "gpt-5.5",
-  systemPrompt: "",
-  models: [],
-  quality: "auto",
-  size: "1:1",
-  count: "1",
-};
-
-export function normalizeBaseUrl(value: string) {
-  return value.trim().replace(/\/+$/, "");
-}
-
-export function buildApiUrl(baseUrl: string, path: string) {
-  const normalizedBaseUrl = normalizeBaseUrl(baseUrl);
-  const apiBaseUrl = normalizedBaseUrl.endsWith("/v1") ? normalizedBaseUrl : `${normalizedBaseUrl}/v1`;
-  return `${apiBaseUrl}${path}`;
-}