Initial Rails 8 scaffold for whetrails

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/assets/stylesheets/application.css

@@ -0,0 +1,10 @@
+/*
+ * This is a manifest file that'll be compiled into application.css.
+ *
+ * With Propshaft, assets are served efficiently without preprocessing steps. You can still include
+ * application-wide styles in this file, but keep in mind that CSS precedence will follow the standard
+ * cascading order, meaning styles declared later in the document or manifest will override earlier ones,
+ * depending on specificity.
+ *
+ * Consider organizing styles into separate files for maintainability.
+ */