refactor(frontend): P1-P2 架构统一 — utils/hooks/api 模块化

P1:
- utils/storage.ts、theme.ts、validate.ts + index 统一出口
- request/store/useTheme 接入 storage；清零 confirm/alert
- PipelineManager、TerminalAuditTab 拆分子模块（<700行红线）

P2:
- api/monitor、api/deploy 子目录化
- hooks/api 扩展：servers/pipelines/alerts/audit/sessionCommands
- PipelineManager、AuditOperationsTab 接入 TanStack Query

frontend/src/utils/validate.ts

@@ -0,0 +1,42 @@
+// 通用表单校验 // Logan.Li
+
+export function isNotEmpty(value: unknown): boolean {
+  if (value === null || value === undefined) return false;
+  return String(value).trim().length > 0;
+}
+
+export function isValidPort(port: unknown): boolean {
+  const n = Number(port);
+  return Number.isInteger(n) && n > 0 && n <= 65535;
+}
+
+export function isValidIPv4(ip: string): boolean {
+  const parts = ip.trim().split('.');
+  if (parts.length !== 4) return false;
+  return parts.every((p) => {
+    const n = Number(p);
+    return Number.isInteger(n) && n >= 0 && n <= 255 && String(n) === p;
+  });
+}
+
+export function isValidHostname(host: string): boolean {
+  const h = host.trim();
+  if (!h) return false;
+  return /^[a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?(\.[a-zA-Z0-9]([a-zA-Z0-9-]{0,61}[a-zA-Z0-9])?)*$/.test(h);
+}
+
+export function isValidUrl(url: string): boolean {
+  try {
+    const u = new URL(url);
+    return u.protocol === 'http:' || u.protocol === 'https:';
+  } catch {
+    return false;
+  }
+}
+
+export function parsePortList(text: string): number[] {
+  return text
+    .split(',')
+    .map((s) => parseInt(s.trim(), 10))
+    .filter((n) => isValidPort(n));
+}