Rebuild printable roast plans and remove machine-based adjustments

shared/time.js

@@ -15,8 +15,14 @@ export function parseDuration(str) {
   const sign = s.startsWith("-") ? -1 : 1;
   const body = s.replace(/^[+-]/, "");
   const m = body.match(/^(\d+):(\d{1,2})$/);
-  if (m) return sign * (Number(m[1]) * 60 + Number(m[2]));
-  if (/^\d+(\.\d+)?$/.test(body)) return sign * Math.round(Number(body));
+  if (m) {
+    const seconds = Number(m[1]) * 60 + Number(m[2]);
+    return Number(m[2]) < 60 && Number.isSafeInteger(seconds) ? sign * seconds : null;
+  }
+  if (/^\d+(\.\d+)?$/.test(body)) {
+    const seconds = Math.round(Number(body));
+    return Number.isSafeInteger(seconds) ? sign * seconds : null;
+  }
   return null;
 }