Close DV-01–04,07,09,13,14: unify operator-deck UX in server/web.

Standardize neon cyan on #00e8f5, wire SacredPageHeader across Builds/Path Tracer/LOTL, dedupe Pages.css, align Path Tracer chrome, drop dead wealth-deck CSS, add prefers-color-scheme shell + HelpTip, sidebar version from package.json build inject, and Vitest CSS regression guards.

server/web/src/help/authStoragePolicy.ts

@@ -0,0 +1,24 @@
+/**
+ * Cross-tab auth storage policy (document-only).
+ *
+ * Credentials mirror in sessionStorage and localStorage under `aetherforge_auth`.
+ * Reads prefer sessionStorage, then fall back to localStorage (survives tab close).
+ *
+ * Same-tab sync: login/logout dispatch the `aetherforge-auth` CustomEvent so SessionGate,
+ * WebSocketProvider, and PresenceContext re-read credentials without a full reload.
+ *
+ * Cross-tab: intentionally NOT synced via the `storage` event. Logout in tab A clears
+ * localStorage but tab B keeps in-memory session until refresh or a 401. Each tab owns
+ * its WS lifecycle after auth changes in that tab.
+ */
+
+export const AUTH_STORAGE_KEY = 'aetherforge_auth';
+export const AUTH_EXPIRED_FLAG_KEY = 'aetherforge_auth_expired';
+export const AUTH_SYNC_EVENT = 'aetherforge-auth';
+
+/** By policy we never listen to cross-tab `storage` events for auth. */
+export const AUTH_CROSS_TAB_STORAGE_SYNC = false;
+
+export function describeAuthStoragePolicy(): string {
+  return 'dual-write session+local; same-tab aetherforge-auth; no storage-event cross-tab sync';
+}