feat: 新增模型管理功能（供应商 + 模型 CRUD）

- 新增 providers/models 数据库表、迁移和数据访问层
- 新增 15 个后端 API 路由（供应商/模型 CRUD + 连通性测试）
- 新增 AI 服务层（registry.ts: buildProviderRegistry + testProviderConnection）
- 新增前端模型管理页面（Tabs: 供应商/模型，含表格、表单、工具栏）
- 新增前端 hooks（use-providers, use-models）
- 新增共享类型和 MODEL_CAPABILITIES 常量
- 新增 10 个测试文件（66 个测试用例，4 个因 bun test ESM 兼容问题待修复）
- 更新开发文档（architecture, backend, frontend）
- 附带 apply-review 修复：统一错误响应、提取共享常量、清理重复测试

注意：registry.test.ts 中 4 个测试因 bun test 无法解析
createProviderRegistry ESM 导出而失败，详情见 context.md

src/web/pages/models/components/ProviderFormModal.tsx

@@ -0,0 +1,113 @@
+import { App as AntApp, Form, Input, Modal, Select } from "antd";
+import { useEffect } from "react";
+
+import type { CreateProviderRequest, Provider, ProviderType, UpdateProviderRequest } from "../../../../shared/api";
+
+interface FormValues {
+  apiKey: string;
+  baseUrl: string;
+  name: string;
+  type: ProviderType;
+}
+
+interface ProviderFormModalProps {
+  editingProvider: null | Provider;
+  onCancel: () => void;
+  onCreate: (data: CreateProviderRequest) => Promise<unknown>;
+  onOpenChange: (open: boolean) => void;
+  onUpdate: (args: { data: UpdateProviderRequest; id: string }) => Promise<unknown>;
+  open: boolean;
+  submitting: boolean;
+}
+
+const TYPE_OPTIONS = [
+  { label: "OpenAI 兼容", value: "openai-compatible" },
+  { label: "OpenAI", value: "openai" },
+  { label: "Anthropic", value: "anthropic" },
+];
+
+export function ProviderFormModal({
+  editingProvider,
+  onCancel,
+  onCreate,
+  onOpenChange,
+  onUpdate,
+  open,
+  submitting,
+}: ProviderFormModalProps) {
+  const { message } = AntApp.useApp();
+  const [form] = Form.useForm<FormValues>();
+
+  useEffect(() => {
+    if (!open) return;
+    if (editingProvider) {
+      form.setFieldsValue({
+        apiKey: editingProvider.apiKey,
+        baseUrl: editingProvider.baseUrl,
+        name: editingProvider.name,
+        type: editingProvider.type,
+      });
+    } else {
+      form.resetFields();
+    }
+  }, [editingProvider, form, open]);
+
+  const handleFinish = async (values: FormValues) => {
+    try {
+      if (editingProvider) {
+        const reqData: UpdateProviderRequest = {};
+        if (values.name !== editingProvider.name) reqData.name = values.name;
+        if (values.baseUrl !== editingProvider.baseUrl) reqData.baseUrl = values.baseUrl;
+        if (values.apiKey !== editingProvider.apiKey) reqData.apiKey = values.apiKey;
+        if (values.type !== editingProvider.type) reqData.type = values.type;
+        await onUpdate({ data: reqData, id: editingProvider.id });
+        message.success("供应商已更新");
+      } else {
+        const reqData: CreateProviderRequest = {
+          apiKey: values.apiKey,
+          baseUrl: values.baseUrl,
+          name: values.name,
+          type: values.type,
+        };
+        await onCreate(reqData);
+        message.success("供应商已创建");
+      }
+      onOpenChange(false);
+    } catch (err) {
+      if (err instanceof Error) {
+        message.error(err.message);
+      }
+    }
+  };
+
+  return (
+    <Modal
+      confirmLoading={submitting}
+      destroyOnHidden
+      okText="确定"
+      onCancel={onCancel}
+      onOk={() => void form.submit()}
+      open={open}
+      title={editingProvider ? "编辑供应商" : "新建供应商"}
+    >
+      <Form form={form} layout="vertical" onFinish={(values) => void handleFinish(values)}>
+        <Form.Item
+          label="供应商名称"
+          name="name"
+          rules={[{ message: "请输入供应商名称", required: true, whitespace: true }]}
+        >
+          <Input placeholder="请输入供应商名称" />
+        </Form.Item>
+        <Form.Item label="供应商类型" name="type" rules={[{ message: "请选择供应商类型", required: true }]}>
+          <Select options={TYPE_OPTIONS} placeholder="请选择供应商类型" />
+        </Form.Item>
+        <Form.Item label="Base URL" name="baseUrl" rules={[{ message: "请输入 Base URL", required: true }]}>
+          <Input placeholder="https://api.openai.com/v1" />
+        </Form.Item>
+        <Form.Item label="API Key" name="apiKey" rules={[{ message: "请输入 API Key", required: true }]}>
+          <Input.Password placeholder="请输入 API Key" />
+        </Form.Item>
+      </Form>
+    </Modal>
+  );
+}