refactor: 简化模型管理，移除启用/禁用，优化测试和布局

- 移除供应商/模型启用禁用能力，清理DB schema/migration/API/前端
- 供应商测试改为Base URL连通性+/models探测
- 新增POST /api/models/test模型连接测试
- 新增GET /api/providers/options专用供应商选项接口
- 统一工具栏为ModelsToolbar，参考项目管理布局
- 模型弹窗优化：默认能力、响应式3列标签、并排数值
- 前后端正整数校验、供应商下拉loading/error/empty状态
- 表格列宽统一，操作列/名称列固定宽度

tests/server/db/models.test.ts

@@ -5,8 +5,6 @@ import { describe, expect, test } from "bun:test";
 import {
   createModel,
   deleteModel,
-  disableModel,
-  enableModel,
   getModel,
   getModelsByProviderId,
   listModels,
@@ -41,16 +39,12 @@ describe("模型数据访问层", () => {
         providerId,
       });
       expect("error" in result).toBe(false);
-      const model = (
-        result as {
-          model: { capabilities: string[]; enabled: boolean; modelId: string; name: string; providerId: string };
-        }
-      ).model;
+      const model = (result as { model: { capabilities: string[]; modelId: string; name: string; providerId: string } })
+        .model;
       expect(model.name).toBe("GPT-4o");
       expect(model.modelId).toBe("gpt-4o");
       expect(model.providerId).toBe(providerId);
       expect(model.capabilities).toEqual(["text", "reasoning"]);
-      expect(model.enabled).toBe(true);
     });
   });
 
@@ -150,35 +144,6 @@ describe("模型数据访问层", () => {
     });
   });
 
-  test("启用/禁用模型", () => {
-    withDb((db) => {
-      const providerId = seedProvider(db);
-      const created = createModel(db, { capabilities: ["text"], modelId: "gpt-4o", name: "测试", providerId });
-      const id = (created as { model: { id: string } }).model.id;
-
-      const disabled = disableModel(db, id);
-      expect("error" in disabled).toBe(false);
-      expect((disabled as { model: { enabled: boolean } }).model.enabled).toBe(false);
-
-      const enabled = enableModel(db, id);
-      expect("error" in enabled).toBe(false);
-      expect((enabled as { model: { enabled: boolean } }).model.enabled).toBe(true);
-    });
-  });
-
-  test("重复禁用失败", () => {
-    withDb((db) => {
-      const providerId = seedProvider(db);
-      const created = createModel(db, { capabilities: ["text"], modelId: "gpt-4o", name: "测试", providerId });
-      const id = (created as { model: { id: string } }).model.id;
-      disableModel(db, id);
-
-      const result = disableModel(db, id);
-      expect("error" in result).toBe(true);
-      expect((result as unknown as { status: number }).status).toBe(409);
-    });
-  });
-
   test("删除模型", () => {
     withDb((db) => {
       const providerId = seedProvider(db);