Store cookie durations as max_age_seconds

Replace the free-form duration TEXT column with a nullable
max_age_seconds INTEGER on both cookies and cookie_patterns
tables. The SDK detector now sends raw seconds instead of
humanized strings, eliminating locale-dependent comparisons
in the pattern merge worker. Humanization happens at display
time in the widget and console UI.

Signed-off-by: Émile Ré <emile@getprobo.com>

packages/helpers/src/duration.ts

@@ -0,0 +1,33 @@
+// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+const UNITS: [number, string, string][] = [
+  [365 * 24 * 3600, "year", "years"],
+  [30 * 24 * 3600, "month", "months"],
+  [7 * 24 * 3600, "week", "weeks"],
+  [24 * 3600, "day", "days"],
+  [3600, "hour", "hours"],
+  [60, "minute", "minutes"],
+];
+
+export function humanizeSeconds(seconds: number | null): string {
+  if (seconds === null || seconds <= 0) return "session";
+  for (const [unit, singular, plural] of UNITS) {
+    if (seconds >= unit && seconds % unit === 0) {
+      const count = seconds / unit;
+      return `${count} ${count === 1 ? singular : plural}`;
+    }
+  }
+  return `${seconds} seconds`;
+}

packages/helpers/src/index.ts

@@ -109,6 +109,7 @@ export {
   formatDuration,
   parseDate,
 } from "./date";
+export { humanizeSeconds } from "./duration";
 export { getTrustCenterUrl } from "./trustCenter";
 export { detectSocialName } from "./socialUrl";
 export { formatError, type GraphQLError } from "./error";