Migrate to Rais 8.0

- Remove all Rodauth stuff and implement simple custom auth
- Migrate from sprockets to propshaft, hack some bootstrap stuff

db/migrate/20241108175901_create_users.rb

@@ -0,0 +1,11 @@
+class CreateUsers < ActiveRecord::Migration[8.0]
+  def change
+    create_table :users do |t|
+      t.string :email_address, null: false
+      t.string :password_digest, null: false
+
+      t.timestamps
+    end
+    add_index :users, :email_address, unique: true
+  end
+end