Add sync error logging, extend error flash, fix unload saves

- Log workforce sync errors to backend stdout so they appear in docker logs
- Extend error flash from 5s to 15s so errors are readable
- Replace sendBeacon (POST-only) with keepalive fetch (PUT) on unload —
  sendBeacon was hitting 404s on all three unload saves

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

frontend/node_modules/@babel/helper-validator-identifier/lib/keyword.js

@@ -0,0 +1,35 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.isKeyword = isKeyword;
+exports.isReservedWord = isReservedWord;
+exports.isStrictBindOnlyReservedWord = isStrictBindOnlyReservedWord;
+exports.isStrictBindReservedWord = isStrictBindReservedWord;
+exports.isStrictReservedWord = isStrictReservedWord;
+const reservedWords = {
+  keyword: ["break", "case", "catch", "continue", "debugger", "default", "do", "else", "finally", "for", "function", "if", "return", "switch", "throw", "try", "var", "const", "while", "with", "new", "this", "super", "class", "extends", "export", "import", "null", "true", "false", "in", "instanceof", "typeof", "void", "delete"],
+  strict: ["implements", "interface", "let", "package", "private", "protected", "public", "static", "yield"],
+  strictBind: ["eval", "arguments"]
+};
+const keywords = new Set(reservedWords.keyword);
+const reservedWordsStrictSet = new Set(reservedWords.strict);
+const reservedWordsStrictBindSet = new Set(reservedWords.strictBind);
+function isReservedWord(word, inModule) {
+  return inModule && word === "await" || word === "enum";
+}
+function isStrictReservedWord(word, inModule) {
+  return isReservedWord(word, inModule) || reservedWordsStrictSet.has(word);
+}
+function isStrictBindOnlyReservedWord(word) {
+  return reservedWordsStrictBindSet.has(word);
+}
+function isStrictBindReservedWord(word, inModule) {
+  return isStrictReservedWord(word, inModule) || isStrictBindOnlyReservedWord(word);
+}
+function isKeyword(word) {
+  return keywords.has(word);
+}
+
+//# sourceMappingURL=keyword.js.map