feat: add location display for NMs

Closes #1.

app/views/instance/_list.html.erb

@@ -12,6 +12,17 @@
       <div class="meta">
         <h3 class="nm-info">
           <span class="badge">LV<%= nm[:level].to_s.rjust(2, "0") %></span>
+          <% if nm[:x] and nm[:y] %>
+            <span class="map-icon">
+              <%= render partial: "map_icon" %>
+              <div class="map-popup">
+                <div style="position: relative; width: 200px; height: 200px;">
+                  <img src="/maps/<%= @instance.zone %>_fw.jpg" style="width: 200px; z-index: 100;" />
+                  <span class="map-nm-loc" style="position: absolute; left: <%= (nm[:x] / 42.0) * 100.0 %>%; top: <%= (nm[:y] / 42.0) * 100.0 %>%;"></span>
+                </div>
+              </div>
+            </span>
+          <% end %>
           <%= nm[:name] %>
           <% if nm[:drops] %>
             <span title="<%= nm[:drops] %>" style="font-size: 14px;">✨</span>

app/views/instance/_map_icon.html.erb

@@ -0,0 +1,3 @@
+<svg viewBox="0 0 24 24"  xmlns="http://www.w3.org/2000/svg">
+  <path d="M9 20L3 17V4L9 7M9 20L15 17M9 20V7M15 17L21 20V7L15 4M15 17V4M9 7L15 4" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"/>
+</svg>