feat(web): W3-1 shared console routes, nav, api/sse/query-keys and shared components

- routes.ts registers all workspaces under /console (+ detail routes, engine, audit, login)
- api.ts: cookie session first (credentials include, CSRF header), Bearer only with stored key, 401 -> /login
- sse.ts: shared EventSource with ?after=seq catch-up, backoff reconnect, per-type subscribe
- shared components: data-table, filter-bar, detail-sheet, timeline, json-view, confirm-dialog,
  form-field, kv-list, stat-tile, error/loading states; ui tabs and textarea

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/web/app/routes/console/audit.tsx

@@ -0,0 +1,6 @@
+import { WorkspacePlaceholder } from "~/components/console/workspace-placeholder.tsx";
+
+// 占位:路由已在 app/routes.ts 登记,由对应工作区负责实现
+export default function Page() {
+  return <WorkspacePlaceholder />;
+}