refactor: 统一 expect 断言体系，引入共享 ValueMatcher/ContentRules/KeyValueExpect 模型

- 引入共享 ValueMatcher（equals/contains/regex/exists/empty/gt/gte/lt/lte）
- 引入共享 ContentRules 数组（direct/json/css/xpath 提取器）
- 引入共享 KeyValueExpect（动态键值断言，字面量等价 equals）
- maxDurationMs → durationMs: ValueMatcher（所有 checker）
- match → regex（固定无 flags）
- Ping max* → packetLossPercent/avgLatencyMs/maxLatencyMs（ValueMatcher）
- LLM finishReason/rawFinishReason → ValueMatcher
- DB 新增 result: ContentRules
- TCP banner → ContentRules 数组
- 删除旧模块：operator.ts、validate-operator.ts、duration.ts、body.ts、text.ts、output.ts
- 更新全部 checker schema/validate/expect/execute
- 更新 probe-config.schema.json、probes.example.yaml
- 更新 README.md、DEVELOPMENT.md（含 expect 字段选择规范）
- 同步 10 个 delta specs 到主 specs，归档 change

src/server/checker/runner/icmp/execute.ts

@@ -4,8 +4,8 @@ import type { CheckResult, RawTargetConfig } from "../../types";
 import type { CheckerContext, CheckerDefinition, CheckerValidationInput, ResolveContext } from "../types";
 import type { PingExpectConfig, PingStats, PingTargetConfig, ResolvedPingTarget } from "./types";
 
-import { checkDuration } from "../../expect/duration";
 import { errorFailure } from "../../expect/failure";
+import { checkValueMatcher } from "../../expect/matcher";
 import { buildPingCommand } from "./command";
 import { checkAlive, checkAvgLatency, checkMaxLatency, checkPacketLoss } from "./expect";
 import { parsePingOutput } from "./parse";
@@ -140,13 +140,17 @@ function buildStatusDetail(stats: PingStats): string {
 function checkStats(stats: PingStats, expect: PingExpectConfig | undefined, durationMs: number) {
   const aliveResult = checkAlive(stats.alive, expect?.alive ?? true);
   if (!aliveResult.matched) return aliveResult;
-  const packetLossResult = checkPacketLoss(stats.packetLoss, expect?.maxPacketLoss);
+  const packetLossResult = checkPacketLoss(stats.packetLoss, expect?.packetLossPercent);
   if (!packetLossResult.matched) return packetLossResult;
-  const avgLatencyResult = checkAvgLatency(stats.avgLatencyMs, expect?.maxAvgLatencyMs);
+  const avgLatencyResult = checkAvgLatency(stats.avgLatencyMs, expect?.avgLatencyMs);
   if (!avgLatencyResult.matched) return avgLatencyResult;
-  const maxLatencyResult = checkMaxLatency(stats.maxLatencyMs, expect?.maxMaxLatencyMs);
+  const maxLatencyResult = checkMaxLatency(stats.maxLatencyMs, expect?.maxLatencyMs);
   if (!maxLatencyResult.matched) return maxLatencyResult;
-  return checkDuration(durationMs, expect?.maxDurationMs);
+  return checkValueMatcher(durationMs, expect?.durationMs, {
+    message: "durationMs mismatch",
+    path: "durationMs",
+    phase: "duration",
+  });
 }
 
 function formatNumber(value: number): string {