refactor: expect 类型模型重构，Raw/Resolved 双层分离与断言基础设施内聚

- 重命名 ContentRules→ContentExpectations, KeyValueExpect→KeyedExpectations
- 新增 Raw/Resolved 双层模型：resolve 阶段物化为执行计划，store 持久化 Raw 快照
- HTTP body 按需读取：status/headers 失败或无 body expectation 时不读取 body
- 新增 displayValueExpectation() 解包 failure.expected 用户可读展示
- 修复 checkEarlyTimeout 独立 lte/lt 检查，修复 KeyedExpectations JSON Schema
- 新增 expect/value.ts(resolve/check/display)、keyed.ts、content.ts、headers.ts、status.ts
- 删除旧 normalize.ts/matcher.ts/validate-matcher.ts/key-value.ts
- 更新 DEVELOPMENT.md：expect 五层管线表、displayValueExpectation、1.7↔1.10 交叉引用
- 同步 13 个 main specs，归档 refactor-expect-type-model 变更（62/62 tasks）

src/server/checker/runner/cmd/expect.ts

@@ -1,8 +1,8 @@
-import type { ExpectResult } from "../../expect/types";
+import type { ExpectationResult } from "../../expect/types";
 
 import { mismatchFailure } from "../../expect/failure";
 
-export function checkExitCode(exitCode: number, allowed: number[]): ExpectResult {
+export function checkExitCode(exitCode: number, allowed: number[]): ExpectationResult {
   if (!allowed.includes(exitCode)) {
     return {
       failure: mismatchFailure(