Add repo size graph canvas to template

borgweb/borg/static/borg/js/index.js

@@ -5,6 +5,7 @@ function inflateRepo(repo_json, label, template_id, container_id) {
     $(template_copy).find(".repo-latest-backup").html(repo_json.latest_backup);
     $(template_copy).find(".repo-size").html(repo_json.size);
     $(template_copy).find(".repo-recent-errors").html(repo_json.recent_errors);
+    $(template_copy).find(".repo-size-graph").prop("id", `repo-${label}-size-graph`);
 
     let bg_class = "bg-primary";
     if (repo_json.error) {

borgweb/borg/templates/borg/repo-template.html

@@ -17,6 +17,7 @@
             <dt class="col-4">Recent errors:</dt>
             <dd class="repo-recent-errors col-8"></dd>
         </dl>
+        <canvas class="repo-size-graph" width="400" height="200"></canvas>
         </dl>
     </div>
 </script>