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>

omsorgWeb/mitarbeiter-app-legacy/actions/downloads-reorder.php

@@ -0,0 +1,45 @@
+<?php
+require_once __DIR__ . '/../lib/auth.php';
+require_admin();
+
+header('Content-Type: application/json');
+
+if (($_SERVER['HTTP_X_REQUESTED_WITH'] ?? '') !== 'XMLHttpRequest') {
+    echo json_encode(['ok' => false, 'error' => 'forbidden']);
+    exit;
+}
+
+if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
+    echo json_encode(['ok' => false, 'error' => 'method']);
+    exit;
+}
+
+$body  = file_get_contents('php://input');
+$data  = json_decode($body, true);
+$order = $data['order'] ?? null;
+
+if (!is_array($order)) {
+    echo json_encode(['ok' => false, 'error' => 'invalid']);
+    exit;
+}
+
+$ids = array_values(array_filter(array_map('intval', $order), fn($v) => $v > 0));
+
+if (empty($ids)) {
+    echo json_encode(['ok' => true]);
+    exit;
+}
+
+$now  = date('c');
+$pos  = 10;
+$stmt = db()->prepare('UPDATE downloads SET sort_order = ?, updated_at = ? WHERE id = ?');
+
+db()->beginTransaction();
+foreach ($ids as $id) {
+    $stmt->execute([$pos, $now, $id]);
+    $pos += 10;
+}
+db()->commit();
+
+echo json_encode(['ok' => true]);
+exit;