Add donate button to event homepage (#12304)

## Summary of the problem
<!-- Why are these changes being made? What problem does it solve? Link
any related issues to provide more details. -->
closes #12303


## Describe your changes
<!-- Explain your thought process to the solution and provide a quick
summary of the changes. -->
<img width="1604" height="141" alt="Screenshot From 2025-12-02 22-42-51"
src="https://github.com/user-attachments/assets/9c135889-5958-4a2b-a172-4dc685662410"
/>



<!-- If there are any visual changes, please attach images, videos, or
gifs. -->

---------

Co-authored-by: yodalightsabr <yoda@yodacode.xyz>

Author: Luke-Oldenburg

app/views/events/_donate_button.html.erb

@@ -0,0 +1,8 @@
+<%# locals: (event:) %>
+
+<% if event.donation_page_available? && event.is_public && !organizer_signed_in? %>
+  <%= link_to start_donation_donations_path(event), target: "_blank", class: "btn bg-blue flex items-center" do %>
+    <%= inline_icon "purse" %>
+    Donate
+  <% end %>
+<% end %>

app/views/events/_heading.html.erb

@@ -0,0 +1,16 @@
+<%# locals: (event:, event_follow: nil) %>
+
+<h1 class="flex items-center gap-4">
+  <%= yield %>
+  <% admin_tool("badge", "span") do %>
+    <span class="m0 badge bg-muted">
+      #<%= event.id %>
+    </span>
+    <span class="m0 badge bg-muted ml1">
+      SL<%= event.service_level %>
+    </span>
+  <% end %>
+
+  <%= render "events/follow_button", event:, event_follow: %>
+  <%= render "events/donate_button", event: %>
+</h1>

app/views/events/show.html.erb

@@ -27,19 +27,9 @@
   <% end %>
 <% end %>
 
-<h1 class="flex items-center">
+<%= render "events/heading", event: @event, event_follow: @event_follow do %>
   <span class="flex-grow">Home</span>
-  <% admin_tool("p0 m2 badge", "span") do %>
-    <span class="m0 badge bg-muted">
-      #<%= @event.id %>
-    </span>
-    <span class="m0 badge bg-muted ml1">
-      SL<%= @event.service_level %>
-    </span>
-  <% end %>
-
-  <%= render "events/follow_button", event: @event, event_follow: @event_follow %>
-</h1>
+<% end %>
 
 <div class="flex flex-col gap-[20px]" data-controller="event-home">
   <% if organizer_signed_in?(as: :member) %>

app/views/events/transactions.html.erb

@@ -27,19 +27,9 @@
 
 <%= render "events/nav", selected: :transactions %>
 
-<h1 class="flex items-center flex-wrap">
-  <span class="flex-grow mb1">Transactions</span>
-  <% admin_tool("p0 m2 badge", "span") do %>
-    <span class="m0 badge bg-muted">
-      #<%= @event.id %>
-    </span>
-    <span class="m0 badge bg-muted ml1">
-      SL<%= @event.service_level %>
-    </span>
-  <% end %>
-
-  <%= render "events/follow_button", event: @event, event_follow: @event_follow %>
-</h1>
+<%= render "events/heading", event: @event, event_follow: @event_follow do %>
+  <span class="flex-grow">Transactions</span>
+<% end %>
 
 <div class="flex items-center details-horiz details-horiz--lg" style="gap: 8px; pointer-events: none;">
   <% if Flipper.enabled?(:event_home_page_redesign_2024_09_21, @event) %>