Events: add edit/update actions

app/views/events/edit.html.slim

@@ -0,0 +1 @@
+= render "form", event: @event, submit_text: t("helpers.buttons.save"), method: :patch, url: event_path(@event)

app/views/events/show.html.slim

@@ -1,10 +1,12 @@
 .row
   .col
-    h4.mb-3
-      = t("events.index.manage_contests")
+    h4.mb-3 style="margin-top: -1rem;"
+      = t("events.show.manage_contests")
+      a.ms-3.mt-3.btn.btn-primary.mb-4 href=edit_event_path(@event)
+        = t("events.show.modify")
       .float-end
-        a.btn.btn-primary.mb-4 href=new_contest_path(event: @event.id)
-          = t("events.index.new_contest")
+        a.mt-3.btn.btn-primary.mb-4 href=new_contest_path(event: @event.id)
+          = t("events.show.new_contest")
 
 .row.row-cols-1.row-cols-md-3.g-4
   - @contests.each do |contest|