useBlock in the survey frontend to ask users for confirmation

• use a context provider for the filter selection in the compendium frontend
• so that we can upgrade to data routers in both frontends
• so that I can useBlock in the survey frontend to ask users for confirmation when they press the back button while editing...
• and also improve the survey component to allow for rerenders because everything rerenders if navigating away is blocked.....

survey-frontend/src/Prompt.tsx

+import React from "react";
+import { unstable_useBlocker as useBlocker } from "react-router-dom";
+
+// adapted from https://stackoverflow.com/a/75920683
+// also see https://github.com/remix-run/react-router/blob/496b1fe8253643171ecca6e6a945d98386c4eb00/packages/react-router-dom/index.tsx#L1460C4-L1460C4
+// for the unstable_usePrompt implementation in react router itself
+// and https://claritydev.net/blog/display-warning-for-unsaved-form-data-on-page-exit for yet another example
+function Prompt(props) {
+    const block = props.when;
+    const onPageExit = props.onPageExit;
+
+    // NB gives warning in the browser console but thats a bug: https://github.com/remix-run/react-router/issues/10073
+    // apparently the fix of that bug caused a nr of bugs again too...
+    useBlocker(() => {
+        if (block()) {
+            const confirmed = window.confirm(props.message);
+            if (confirmed) {
+                onPageExit();
+            }
+            return !confirmed;
+        }
+        return false;
+    })
+
+    return (
+        <div />
+    );
+}
+
+export default Prompt;