Add bot schedules (routines), open Activity, add Help and a Desktop computer view

Bots create, list, update and delete schedules (cron_jobs, Bun.cron in UTC);
a per-minute cron queues due runs as tasks. Routines, Activity (super admins)
and Help get their own rail aside. Help covers familiar problems, starting
with signing in to Google through Cookie-Editor over the new Desktop (noVNC)
view.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/utils/next-cron-run.ts

@@ -0,0 +1,50 @@
+import { AppData } from "@/src/data/app-data";
+import AppError from "./app-error";
+
+type Params = {
+    /**
+     * A Bun.cron expression: 5 fields or a nickname like `@daily`, in UTC.
+     */
+    schedule: string;
+    /**
+     * Unix ms to look from (the next run is after it). Defaults to now.
+     */
+    from?: number;
+    /**
+     * Refuse schedules that run more often than
+     * `AppData.CronJobMinIntervalMs`. Set when a schedule is saved.
+     */
+    check_interval?: boolean;
+};
+
+/**
+ * The next run of a schedule after `from`, in unix ms, or null when it
+ * never runs again. Throws an `AppError` for an invalid expression (or,
+ * with `check_interval`, one that runs too often).
+ */
+export default function nextCronRun({ schedule, from = Date.now(), check_interval }: Params): number | null {
+    const expression = schedule.trim() as Bun.CronWithAutocomplete;
+    let next: Date | null;
+
+    try {
+        next = Bun.cron.parse(expression, from);
+    } catch {
+        throw new AppError(
+            `"${schedule}" isn't a valid schedule. Use 5 cron fields (minute hour day month weekday, e.g. "0 9 * * MON-FRI") or a nickname like @daily.`,
+        );
+    }
+
+    if (!next) return null;
+
+    if (check_interval) {
+        const after = Bun.cron.parse(expression, next);
+
+        if (after && after.getTime() - next.getTime() < AppData.CronJobMinIntervalMs) {
+            throw new AppError(
+                `"${schedule}" runs too often. Leave at least ${Math.round(AppData.CronJobMinIntervalMs / 60000)} minutes between runs.`,
+            );
+        }
+    }
+
+    return next.getTime();
+}