fix: remove duplicate sessions key breaking Hugo build

Duplicate `sessions:` key in simple-py.md front matter failed the
production build. Also reformats single.html SVG per prettier.

Assisted-by: ClaudeCode:claude-opus-4.8

Author: henryiii

content/events/simple-py.md

@@ -113,7 +113,6 @@ schedule:
       - time: "1:30"
         title: "Other tools (2)"
         duration: "15 mins"
-        sessions:
         sessions:
           - title: "Shipping to distros"
             duration: "15 mins"

layouts/events/single.html

@@ -68,8 +68,26 @@ <h2 class="schedule-day-title">{{ .day }}</h2>
                     <a class="session-title" href="{{ .link }}">{{ .title }}</a>
                     {{- else }}
                     <span class="session-title">{{ .title }}</span>
-                    {{- end -}}
-                    {{- with .slides }}<a class="session-slides" href="{{ . }}" title="Slides" target="_blank" rel="noopener"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" aria-hidden="true"><rect x="2" y="3" width="20" height="14" rx="2"/><line x1="8" y1="21" x2="16" y2="21"/><line x1="12" y1="17" x2="12" y2="21"/></svg></a>{{- end }}
+                    {{- end -}} {{- with .slides }}<a
+                      class="session-slides"
+                      href="{{ . }}"
+                      title="Slides"
+                      target="_blank"
+                      rel="noopener"
+                      ><svg
+                        xmlns="http://www.w3.org/2000/svg"
+                        viewBox="0 0 24 24"
+                        fill="none"
+                        stroke="currentColor"
+                        stroke-width="2"
+                        stroke-linecap="round"
+                        stroke-linejoin="round"
+                        aria-hidden="true"
+                      >
+                        <rect x="2" y="3" width="20" height="14" rx="2" />
+                        <line x1="8" y1="21" x2="16" y2="21" />
+                        <line x1="12" y1="17" x2="12" y2="21" /></svg></a
+                    >{{- end }}
                   </span>
                   {{- with .duration }}<span class="session-duration"
                     >{{ . }}</span