Add web front-end and fix API issues

node_modules/rxjs/dist/cjs/internal/operators/distinctUntilKeyChanged.js

@@ -0,0 +1,9 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.distinctUntilKeyChanged = void 0;
+var distinctUntilChanged_1 = require("./distinctUntilChanged");
+function distinctUntilKeyChanged(key, compare) {
+    return distinctUntilChanged_1.distinctUntilChanged(function (x, y) { return (compare ? compare(x[key], y[key]) : x[key] === y[key]); });
+}
+exports.distinctUntilKeyChanged = distinctUntilKeyChanged;
+//# sourceMappingURL=distinctUntilKeyChanged.js.map