chore: incidental working-tree changes (not from the versioning work)

Changes already present in the working tree at the time of the versioning
commit, committed here so nothing is left dangling:

- index.js: template PUT preserves the untouched field (?? existing) and the
  preview handler tolerates a null/empty test_object
- update-deployed.sh: detect and restart a pm2-managed app process, and don't
  hard-fail when no bare Node process is found

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

index.js

@@ -606,14 +606,13 @@ app.post("/workshop/:structure_id/template", (req, res) => {
 });
 
 app.put("/workshop/:structure_id/template/:template_id", (req, res) => {
-  let id = req.params.template_id;
+  const id = req.params.template_id;
-  let content = req.body.content;
+  const template = model.getTemplate(id);
-  let test_object = req.body.test_object;
 
   model.updateTemplate({
-    ...model.getTemplate(id),
+    ...template,
-    content,
+    content: req.body.content ?? template.content,
-    test_object,
+    test_object: req.body.test_object ?? template.test_object,
   });
 
   return res.send("good");
@@ -632,9 +631,12 @@ app.get("/workshop/:structure_id/template/:template_id/preview", (req, res) => {
   const template = model.getTemplate(req.params.template_id);
   const struct = model.getStructure(req.params.structure_id);
 
-  const context = vm.createContext({ it: null });
+  const context = vm.createContext({ it: {} });
+  if (template.test_object) {
     vm.runInContext(template.test_object, context);
+  }
 
+  context.it ??= {};
   context.it.route = makeRoute(struct);
 
   return res.send(

update-deployed.sh

@@ -70,6 +70,25 @@ else
   echo "Dependencies unchanged; skipping npm install."
 fi
 
+PM2_TARGET=""
+if command -v pm2 >/dev/null 2>&1; then
+  PM2_TARGET="$(pm2 jlist 2>/dev/null | APP_DIR="$APP_DIR" node -e '
+    let input = "";
+    process.stdin.on("data", chunk => input += chunk);
+    process.stdin.on("end", () => {
+      try {
+        const appDir = process.env.APP_DIR;
+        const processes = JSON.parse(input);
+        const match = processes.find(process => {
+          const env = process.pm2_env || {};
+          return env.pm_cwd === appDir || env.pm_exec_path === `${appDir}/index.js`;
+        });
+        if (match) process.stdout.write(String(match.pm_id));
+      } catch (_) {}
+    });
+  ' || true)"
+fi
+
 mapfile -t APP_PIDS < <(
   for process_dir in /proc/[0-9]*; do
     [[ "$(readlink "$process_dir/cwd" 2>/dev/null || true)" == "$APP_DIR" ]] || continue
@@ -78,35 +97,31 @@ mapfile -t APP_PIDS < <(
   done
 )
 
-if [[ "${#APP_PIDS[@]}" -eq 0 ]]; then
+APP_PID="${APP_PIDS[0]:-}"
-  echo "No running Node process found for $APP_DIR; refusing to guess how to start it." >&2
-  exit 1
-fi
-
-APP_PID="${APP_PIDS[0]}"
 SERVICE=""
 
-while IFS= read -r unit; do
+if [[ -n "$APP_PID" ]]; then
+  while IFS= read -r unit; do
     [[ -n "$unit" ]] || continue
     if [[ "$(systemctl show -p MainPID --value "$unit" 2>/dev/null || true)" == "$APP_PID" ]]; then
       SERVICE="$unit"
       break
     fi
-done < <(systemctl list-units --type=service --all --no-legend --plain 2>/dev/null | awk '{print $1}')
+  done < <(systemctl list-units --type=service --all --no-legend --plain 2>/dev/null | awk '{print $1}')
+fi
 
 if [[ -n "$SERVICE" ]]; then
   echo "Restarting systemd service $SERVICE..."
   systemctl restart "$SERVICE"
   systemctl is-active --quiet "$SERVICE"
   systemctl --no-pager --full status "$SERVICE" | sed -n '1,12p'
-elif command -v pm2 >/dev/null 2>&1 && pm2 pid all 2>/dev/null | grep -qx "$APP_PID"; then
+elif [[ -n "$PM2_TARGET" ]]; then
-  echo "Restarting PM2 process $APP_PID..."
+  echo "Restarting PM2 process $PM2_TARGET..."
-  pm2 restart "$APP_PID" --update-env
+  pm2 restart "$PM2_TARGET" --update-env
-  pm2 show "$APP_PID"
+  pm2 show "$PM2_TARGET"
 else
-  echo "Found Node PID $APP_PID, but it is not managed by systemd or PM2." >&2
+  echo "Could not find a systemd or PM2 app configured for $APP_DIR." >&2
   echo "The code was updated from $OLD_HEAD to $NEW_HEAD, but the process was not restarted." >&2
-  echo "Refusing to kill it without knowing the correct startup mechanism." >&2
   exit 1
 fi