Refactor app in to its own slice

slices/main/templates/workouts/index.html.slim

@@ -0,0 +1,14 @@
+- context.content_for(:title, "Hikes | ")
+
+div class="mb-12 prose dark:prose-invert max-w-prose mx-auto text-gray-800 dark:text-gray-200"
+  h1 🥾 Hikes
+
+div class="prose dark:prose-invert max-w-prose mx-auto"
+  - workouts_by_year.each do |year, workouts|
+    h3= year
+    h1= "#{workouts.map{|w| w.distance }.sum.round} km — #{workouts.map{|w| w.duration / 60 / 60 }.sum.round} hours"
+    div class="grid grid-cols-3 gap-4 mb-4 max-w-prose mx-auto"
+      - workouts.each do |workout|
+        == workout.path
+
+div class="max-w-screen-md mx-auto border-t border-solid border-gray-200 dark:border-gray-600"