test(webapp): use relative fixture dates in runs cursor pagination tests

The fixtures pinned createdAt to 2026-06-04, and listRuns applies the
default 7 day window when no time filter is given. The fixtures aged out
of that window on 2026-06-11, turning every CI run red for a test the
branch never touched. Relative dates keep the fixtures inside the window
permanently.

Author: ericallam

apps/webapp/test/runsRepositoryCursor.test.ts

@@ -70,7 +70,7 @@ describe("RunsRepository cursor pagination", () => {
         "dddddddddddddddddddddddd",
         "eeeeeeeeeeeeeeeeeeeeeeee",
       ];
-      const base = new Date("2026-06-04T16:55:07.000Z").getTime();
+      const base = Date.now() - 60 * 60 * 1000; // relative, so fixtures never age out of the default 7d window
       for (let i = 0; i < ids.length; i++) {
         await prisma.taskRun.create({
           data: {
@@ -160,7 +160,7 @@ describe("RunsRepository cursor pagination", () => {
         "bbbbbbbbbbbbbbbbbbbbbbbb",
         "cccccccccccccccccccccccc",
       ];
-      const base = new Date("2026-06-04T16:55:07.000Z").getTime();
+      const base = Date.now() - 60 * 60 * 1000; // relative, so fixtures never age out of the default 7d window
       for (let i = 0; i < ids.length; i++) {
         await prisma.taskRun.create({
           data: {
@@ -255,7 +255,7 @@ describe("RunsRepository cursor pagination", () => {
         "bbbbbbbbbbbbbbbbbbbbbbbb",
         "cccccccccccccccccccccccc",
       ];
-      const base = new Date("2026-06-04T16:55:07.000Z").getTime();
+      const base = Date.now() - 60 * 60 * 1000; // relative, so fixtures never age out of the default 7d window
       for (let i = 0; i < ids.length; i++) {
         await prisma.taskRun.create({
           data: {
@@ -339,7 +339,7 @@ describe("RunsRepository cursor pagination", () => {
         "dddddddddddddddddddddddd",
         "eeeeeeeeeeeeeeeeeeeeeeee",
       ];
-      const base = new Date("2026-06-04T16:55:07.000Z").getTime();
+      const base = Date.now() - 60 * 60 * 1000; // relative, so fixtures never age out of the default 7d window
       for (let i = 0; i < ids.length; i++) {
         await prisma.taskRun.create({
           data: {
@@ -458,7 +458,7 @@ describe("RunsRepository cursor pagination", () => {
         "bbbbbbbbbbbbbbbbbbbbbbbb",
         "cccccccccccccccccccccccc",
       ];
-      const base = new Date("2026-06-04T16:55:07.000Z").getTime();
+      const base = Date.now() - 60 * 60 * 1000; // relative, so fixtures never age out of the default 7d window
       for (let i = 0; i < ids.length; i++) {
         await prisma.taskRun.create({
           data: {