test(cache): 修复CacheConfigTest边界值测试

- 修改 shouldVerifyCacheManager_withMaximumIntegerTtl 为 shouldVerifyCacheManager_withMaximumAllowedTtl
- 使用正确的最大TTL值（10080分钟，7天）而不是 Integer.MAX_VALUE
- 新增 shouldThrowException_whenTtlExceedsMaximum 测试验证边界检查
- 所有1266个测试用例通过
- 覆盖率: 指令81.89%, 行88.48%, 分支51.55%

docs: 添加项目状态报告
- 生成 PROJECT_STATUS_REPORT.md 详细记录项目当前状态
- 包含质量指标、已完成功能、待办事项和技术债务

frontend/shared/auth.ts

@@ -0,0 +1,41 @@
+export const parseUserId = (value: unknown): number | null => {
+  if (typeof value === 'number' && Number.isFinite(value)) {
+    return value
+  }
+  if (typeof value === 'string' && value.trim() !== '') {
+    const parsed = Number(value)
+    return Number.isFinite(parsed) ? parsed : null
+  }
+  return null
+}
+
+export const getUserIdFromToken = (token?: string | null): number | null => {
+  if (!token) {
+    return null
+  }
+
+  const parts = token.split('.')
+  if (parts.length < 2) {
+    return null
+  }
+
+  try {
+    const payload = JSON.parse(decodeBase64Url(parts[1]))
+    return parseUserId(payload?.userId)
+  } catch {
+    return null
+  }
+
+  return null
+}
+
+const decodeBase64Url = (input: string): string => {
+  const normalized = input.replace(/-/g, '+').replace(/_/g, '/')
+  const padded = normalized.padEnd(Math.ceil(normalized.length / 4) * 4, '=')
+  const binary = atob(padded)
+  let result = ''
+  for (let i = 0; i < binary.length; i += 1) {
+    result += String.fromCharCode(binary.charCodeAt(i))
+  }
+  return decodeURIComponent(escape(result))
+}