refactor: 将 memory checker 重命名为 mem

- 类型标识符 memory → mem
- 类名 MemoryChecker → MemChecker
- 内部类型名统一 Memory* → Mem*
- 内部函数名统一 *Memory* → *Mem*
- 目录重命名 memory/ → mem/（源码、测试、文档）
- 配置键 memory: → mem:
- 重新生成 probe-config.schema.json
- 保留中文"内存"用户提示

破坏性变更：无向后兼容

tests/server/checker/runner/mem/expect.test.ts

@@ -0,0 +1,149 @@
+import { describe, expect, test } from "bun:test";
+
+import {
+  checkActiveBytes,
+  checkActivePercent,
+  checkAvailableBytes,
+  checkAvailablePercent,
+  checkBuffcacheBytes,
+  checkFreeBytes,
+  checkFreePercent,
+  checkSwapFreeBytes,
+  checkSwapTotalBytes,
+  checkSwapUsagePercent,
+  checkSwapUsedBytes,
+  checkTotalBytes,
+  checkUsagePercent,
+  checkUsedBytes,
+  checkUsedPercent,
+} from "../../../../../src/server/checker/runner/mem/expect";
+
+describe("Mem expect checks - 百分比字段", () => {
+  test("checkUsagePercent 匹配", () => {
+    expect(checkUsagePercent(50, { lte: 85 }).matched).toBe(true);
+  });
+
+  test("checkUsagePercent 不匹配", () => {
+    const result = checkUsagePercent(90, { lte: 85 });
+    expect(result.matched).toBe(false);
+    expect(result.failure?.phase).toBe("usage");
+  });
+
+  test("checkUsedPercent 匹配", () => {
+    expect(checkUsedPercent(75, { lte: 80 }).matched).toBe(true);
+  });
+
+  test("checkUsedPercent 不匹配", () => {
+    const result = checkUsedPercent(85, { lte: 80 });
+    expect(result.matched).toBe(false);
+    expect(result.failure?.phase).toBe("used");
+  });
+
+  test("checkFreePercent 匹配", () => {
+    expect(checkFreePercent(25, { gte: 15 }).matched).toBe(true);
+  });
+
+  test("checkFreePercent 不匹配", () => {
+    const result = checkFreePercent(10, { gte: 15 });
+    expect(result.matched).toBe(false);
+    expect(result.failure?.phase).toBe("free");
+  });
+
+  test("checkActivePercent 匹配", () => {
+    expect(checkActivePercent(50, { lte: 85 }).matched).toBe(true);
+  });
+
+  test("checkAvailablePercent 匹配", () => {
+    expect(checkAvailablePercent(50, { gte: 20 }).matched).toBe(true);
+  });
+
+  test("undefined matcher 直接通过", () => {
+    expect(checkUsagePercent(99.9, undefined).matched).toBe(true);
+    expect(checkFreePercent(0, undefined).matched).toBe(true);
+  });
+});
+
+describe("Mem expect checks - 字节字段", () => {
+  test("checkActiveBytes 匹配", () => {
+    expect(checkActiveBytes(4294967296, { lte: 8589934592 }).matched).toBe(true);
+  });
+
+  test("checkUsedBytes 不匹配", () => {
+    const result = checkUsedBytes(10737418240, { lte: 8589934592 });
+    expect(result.matched).toBe(false);
+    expect(result.failure?.phase).toBe("usedBytes");
+  });
+
+  test("checkFreeBytes 匹配", () => {
+    expect(checkFreeBytes(4294967296, { gte: 2147483648 }).matched).toBe(true);
+  });
+
+  test("checkAvailableBytes 匹配", () => {
+    expect(checkAvailableBytes(6442450944, { gte: 4294967296 }).matched).toBe(true);
+  });
+
+  test("checkTotalBytes 匹配", () => {
+    expect(checkTotalBytes(17179869184, { gte: 8589934592 }).matched).toBe(true);
+  });
+});
+
+describe("Mem expect checks - swap 字段", () => {
+  test("checkSwapUsagePercent null 通过 gte 检查 (Number(null)=0)", () => {
+    expect(checkSwapUsagePercent(null, { gte: 0 }).matched).toBe(true);
+  });
+
+  test("checkSwapUsagePercent null 不匹配大于 0 的 gte", () => {
+    const result = checkSwapUsagePercent(null, { gte: 1 });
+    expect(result.matched).toBe(false);
+    expect(result.failure?.phase).toBe("swapUsage");
+  });
+
+  test("checkSwapUsagePercent 有值时正常匹配", () => {
+    expect(checkSwapUsagePercent(50, { lte: 80 }).matched).toBe(true);
+  });
+
+  test("checkSwapUsagePercent 有值时不匹配", () => {
+    const result = checkSwapUsagePercent(90, { lte: 80 });
+    expect(result.matched).toBe(false);
+  });
+
+  test("checkSwapUsedBytes null 通过 gte:0 (Number(null)=0)", () => {
+    expect(checkSwapUsedBytes(null, { gte: 0 }).matched).toBe(true);
+  });
+
+  test("checkSwapUsedBytes 0 通过 gte:0", () => {
+    expect(checkSwapUsedBytes(0, { gte: 0 }).matched).toBe(true);
+  });
+
+  test("checkSwapFreeBytes null 通过 gte:0", () => {
+    expect(checkSwapFreeBytes(null, { gte: 0 }).matched).toBe(true);
+  });
+
+  test("checkSwapTotalBytes null 匹配 equals:null", () => {
+    expect(checkSwapTotalBytes(null, { equals: null }).matched).toBe(true);
+  });
+
+  test("checkSwapTotalBytes 0 匹配 equals:0", () => {
+    expect(checkSwapTotalBytes(0, { equals: 0 }).matched).toBe(true);
+  });
+
+  test("checkSwapTotalBytes null 不匹配 equals:0", () => {
+    expect(checkSwapTotalBytes(null, { equals: 0 }).matched).toBe(false);
+  });
+});
+
+describe("Mem expect checks - buffcacheBytes", () => {
+  test("checkBuffcacheBytes 有值时匹配", () => {
+    expect(checkBuffcacheBytes(1073741824, { lte: 2147483648 }).matched).toBe(true);
+  });
+
+  test("checkBuffcacheBytes null 通过 gte:0 (Number(null)=0)", () => {
+    expect(checkBuffcacheBytes(null, { gte: 0 }).matched).toBe(true);
+  });
+
+  test("checkBuffcacheBytes null 不匹配 gte:1", () => {
+    const result = checkBuffcacheBytes(null, { gte: 1 });
+    expect(result.matched).toBe(false);
+    expect(result.failure?.phase).toBe("buffcacheBytes");
+  });
+});