Add PDF modal and selectedPost setter

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

node_modules/postcss/lib/parse.d.ts

@@ -0,0 +1,9 @@
+import { Parser } from './postcss.js'
+
+interface Parse extends Parser {
+  default: Parse
+}
+
+declare const parse: Parse
+
+export = parse