Add @tailwindcss/forms plugin and improve application form UX

Install @tailwindcss/forms to fix missing padding on form inputs across
the app. Move the Application Type selector earlier in the new application
form (after slug, before description) so it gates type-specific fields
sooner. On the edit page, replace the confusing disabled dropdown with a
read-only badge since the type can't be changed after creation.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/assets/tailwind/application.css

@@ -1 +1,3 @@
 @import "tailwindcss";
+@plugin "@tailwindcss/forms";
+@custom-variant dark (&:where(.dark, .dark *));