Add PDF modal and selectedPost setter

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

node_modules/browserslist/error.d.ts

@@ -0,0 +1,7 @@
+declare class BrowserslistError extends Error {
+  constructor(message: any)
+  name: 'BrowserslistError'
+  browserslist: true
+}
+
+export = BrowserslistError