Add base form styles

We're using the official Tailwind forms plugin now. These "base
form" styles will add onto what Tailwind gives us, the idea is that
these styles will get applied globally. If we need to add further
customizations (not globally) then they should be in another stylesheet
related to where it's being used, if that makes sense. Only global form
style changes should go in here.

For reference, following the pattern here:
tailwindlabs/tailwindcss-forms#33 (comment)

Refs: #3128

app/javascript/stylesheets/base_forms.css

@@ -0,0 +1,32 @@
+@layer base {
+    input[type="text"],
+    input[type="password"],
+    input[type="email"],
+    input[type="number"],
+    input[type="url"],
+    input[type="date"],
+    input[type="datetime-local"],
+    input[type="month"],
+    input[type="week"],
+    input[type="time"],
+    input[type="search"],
+    input[type="tel"],
+    select,
+    select[multiple],
+    textarea {
+        @apply rounded border-gray-400 w-full focus:border-energetic-blue focus:ring-energetic-blue
+    }
+
+    input[type="checkbox"], input[type="radio"] {
+        @apply focus:ring-transparent text-energetic-blue mr-2
+    }
+
+    input[type="text"]:disabled, input[type="email"]:disabled {
+        @apply text-gray-400 bg-gray-100
+    }
+
+    input[type="checkbox"]:disabled, input[type="radio"]:disabled {
+        @apply text-gray-400
+    }
+}
+