fix(v13): V13 审计 6 项修复 — TrajectoryRecorder注册 + industryStore接入 + 知识搜索 + webhook标注 + structured UI + persistent注释

FIX-01: TrajectoryRecorderMiddleware 注册到 create_middleware_chain() (@650优先级)
FIX-02: industryStore 接入 ButlerPanel 行业专长展示 + 自动拉取
FIX-03: 桌面端知识库搜索 saas-knowledge mixin + VikingPanel SaaS KB UI
FIX-04: webhook 迁移标注 deprecated + 添加 down migration 注释
FIX-05: Admin Knowledge 添加结构化数据 Tab (CRUD + 行浏览)
FIX-06: PersistentMemoryStore 精化 dead_code 标注 (完整迁移留后续)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

crates/zclaw-saas/migrations/20260403000002_webhooks.sql

@@ -1,3 +1,7 @@
+-- NOTE: DEPRECATED — These tables are defined but NOT consumed by any Rust code.
+-- Kept for schema compatibility. Will be removed in a future cleanup pass.
+-- See: V13 audit FIX-04
+
 -- Webhook subscriptions: external endpoints that receive event notifications
 CREATE TABLE IF NOT EXISTS webhook_subscriptions (
     id TEXT PRIMARY KEY,
@@ -26,3 +30,10 @@ CREATE TABLE IF NOT EXISTS webhook_deliveries (
 CREATE INDEX IF NOT EXISTS idx_webhook_subscriptions_account ON webhook_subscriptions(account_id);
 CREATE INDEX IF NOT EXISTS idx_webhook_subscriptions_events ON webhook_subscriptions USING gin(events);
 CREATE INDEX IF NOT EXISTS idx_webhook_deliveries_pending ON webhook_deliveries(subscription_id) WHERE delivered_at IS NULL;
+
+-- === DOWN MIGRATION ===
+-- DROP INDEX IF EXISTS idx_webhook_deliveries_pending;
+-- DROP INDEX IF EXISTS idx_webhook_subscriptions_events;
+-- DROP INDEX IF EXISTS idx_webhook_subscriptions_account;
+-- DROP TABLE IF EXISTS webhook_deliveries;
+-- DROP TABLE IF EXISTS webhook_subscriptions;