feat: page history diff (#1891)

* Show actual history changes
* V2 - WIP
* feat: page history diff
* fix: exclude content from history listing

---------

Co-authored-by: Jason Norwood-Young <jason@10layer.com>

apps/client/src/features/page-history/hooks/use-history-reset.ts

@@ -0,0 +1,24 @@
+import { useAtom } from "jotai";
+import { useEffect } from "react";
+import {
+  activeHistoryIdAtom,
+  activeHistoryPrevIdAtom,
+  diffCountsAtom,
+} from "@/features/page-history/atoms/history-atoms";
+
+/**
+ * Resets history state when pageId changes.
+ * Clears active selection and diff counts.
+ */
+export function useHistoryReset(pageId: string) {
+  const [, setActiveHistoryId] = useAtom(activeHistoryIdAtom);
+  const [, setActiveHistoryPrevId] = useAtom(activeHistoryPrevIdAtom);
+  const [, setDiffCounts] = useAtom(diffCountsAtom);
+
+  useEffect(() => {
+    setActiveHistoryId("");
+    setActiveHistoryPrevId("");
+    // @ts-ignore
+    setDiffCounts(null);
+  }, [pageId, setActiveHistoryId, setActiveHistoryPrevId, setDiffCounts]);
+}