Reorganize into monorepo layout, move mitarbeiter-app to legacy reference

Consolidates the previously separate omsorgapp and omsorgCore repos
(each had their own nested .git with GitHub history) plus the old
root-level website/mitarbeiter-app into a single monorepo, matching
the structure already documented in the root CLAUDE.md. Also moves
the PHP employee app aside as omsorgWeb/mitarbeiter-app-legacy/ to
serve as a template for a ground-up rewrite.

Fixes .gitignore in the same pass: the config-secrets/uploads/data
patterns were unanchored (relative to repo root, not depth-agnostic),
so they silently stopped matching once the app moved under omsorgWeb/.
Patterns are now **/-prefixed and cover both mitarbeiter-app and
mitarbeiter-app-legacy, keeping DB/SMTP credentials and uploaded
employee documents out of version control.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

omsorgapp/src/layouts/AppLayout.jsx

@@ -0,0 +1,31 @@
+import Sidebar from "../components/Sidebar";
+import Header from "../components/Header";
+
+export default function AppLayout({
+  children,
+  activePage,
+  onNavigate,
+}) {
+  return (
+    <div className="layout">
+
+      <Sidebar
+        activePage={activePage}
+        onNavigate={onNavigate}
+      />
+
+      <div className="layout-content">
+
+        <Header />
+
+        <main className="page-content">
+
+          {children}
+
+        </main>
+
+      </div>
+
+    </div>
+  );
+}