feat: 配置变量系统与 target id/name 双字段标识

- 新增顶层 variables 段支持 string/number/boolean 字面量
- target 字符串字段支持 、、{...} 转义语法
- 变量解析优先级: variables -> process.env -> 默认值 -> 报错
- 完整引用保留原始类型，部分引用拼接为字符串
- 变量替换在 YAML 解析后、AJV 校验前执行
- 替换仅作用于 targets，跳过 id/type 字段
- target 新增必填 id 字段作为唯一标识，name 改为可选展示名称
- 数据库存储/API/前端全面迁移到 id 标识
- 统一 checker 运行时类型检查为 es-toolkit predicates
- 同步 delta specs 到主 specs，归档 config-variables 变更

tests/server/checker/runner/http/runner.test.ts

@@ -166,6 +166,7 @@ describe("HttpChecker", () => {
         method: overrides.method ?? "GET",
         url: overrides.url ?? `${baseUrl}/ok`,
       },
+      id: "test-http",
       intervalMs: 60000,
       name: "test-http",
       timeoutMs: overrides.timeoutMs ?? 5000,
@@ -850,6 +851,7 @@ describe("HttpChecker.resolve", () => {
     const errors = validateHttpTarget({
       expect: { status: ["abc"] },
       http: { url: "https://example.com" },
+      id: "test",
       name: "test",
       type: "http",
     });
@@ -858,7 +860,7 @@ describe("HttpChecker.resolve", () => {
 
   test("ignoreSSL 默认值为 false", () => {
     const result = checker.resolve(
-      { http: { url: "https://example.com" }, name: "test", type: "http" },
+      { http: { url: "https://example.com" }, id: "test", name: "test", type: "http" },
       makeResolveContext(),
     );
     expect(result.http.ignoreSSL).toBe(false);
@@ -866,7 +868,7 @@ describe("HttpChecker.resolve", () => {
 
   test("maxRedirects 默认值为 0", () => {
     const result = checker.resolve(
-      { http: { url: "https://example.com" }, name: "test", type: "http" },
+      { http: { url: "https://example.com" }, id: "test", name: "test", type: "http" },
       makeResolveContext(),
     );
     expect(result.http.maxRedirects).toBe(0);
@@ -874,7 +876,13 @@ describe("HttpChecker.resolve", () => {
 
   test("合法 status 范围模式通过校验", () => {
     const result = checker.resolve(
-      { expect: { status: ["2xx", 301] }, http: { url: "https://example.com" }, name: "test", type: "http" },
+      {
+        expect: { status: ["2xx", 301] },
+        http: { url: "https://example.com" },
+        id: "test",
+        name: "test",
+        type: "http",
+      },
       makeResolveContext(),
     );
     expect(result.expect?.status).toEqual(["2xx", 301]);
@@ -882,7 +890,12 @@ describe("HttpChecker.resolve", () => {
 
   test("显式 ignoreSSL 和 maxRedirects 正确解析", () => {
     const result = checker.resolve(
-      { http: { ignoreSSL: true, maxRedirects: 3, url: "https://example.com" }, name: "test", type: "http" },
+      {
+        http: { ignoreSSL: true, maxRedirects: 3, url: "https://example.com" },
+        id: "test",
+        name: "test",
+        type: "http",
+      },
       makeResolveContext(),
     );
     expect(result.http.ignoreSSL).toBe(true);