feat(FN-3785): add standalone HTML rendering and export routes for reports

Adds a complete HTML rendering and export pipeline to the fusion-plugin-reports plugin, including a standalone HTML renderer with template and stylesheet support, new export routes (`/api/reports/:id/export/html`) that persist rendered HTML to the store, and plugin-type support for non-JSON route re

Fusion-Task-Id: FN-3785

plugins/fusion-plugin-reports/src/render/escape.ts

@@ -0,0 +1,12 @@
+export function escapeHtml(input: string): string {
+  return input
+    .replaceAll("&", "&")
+    .replaceAll("<", "&lt;")
+    .replaceAll(">", "&gt;")
+    .replaceAll('"', "&quot;")
+    .replaceAll("'", "&#39;");
+}
+
+export function escapeAttr(input: string): string {
+  return escapeHtml(input).replaceAll("`", "&#96;");
+}