完善 readiness、发布追溯与敏感治理（07-15-production-trust-closeout-cleanup）

client/src/main.tsx

@@ -10,6 +10,8 @@ import { AppRouter } from "./router";
 import { clearPwaRuntimeCaches, registerPwaIfEnabled } from "./pwa";
 import "./index.css";
 
+document.documentElement.dataset.buildSha = String(import.meta.env.VITE_BUILD_SHA || "development").slice(0, 12);
+
 const CHUNK_RELOAD_ATTEMPTED_KEY = "hyb_oa_chunk_reload_attempted";
 const CHUNK_LOAD_ERROR_PATTERNS = [
   "chunkloaderror",