fix(ingest): retire a day-precision row on the clock the app reads it on

Three parsers decide currency against ctx.now, because their page has no
"ongoing" heading worth trusting: bawiki.ts, and the Fate/Grand Order and
Infinity Nikki branches of fandom.ts. All three compared Date.parse(endsAt) to
now, and all three publish day-precision ends — so the comparison was against
the 00:00Z placeholder, which § Domain rules says is not an instant and nothing
may read literally.

clockFor already knows that and resolves such a boundary to the reset opening
that game-day on the reader's server. The parsers did not, so the feed retired
a row up to nine hours before the app, the countdown and the game all agreed it
was over. On the pinned Infinity Nikki fixture, "Inspiration Burst" left the
feed at 2026-08-22T01:00Z while clockFor still called it live for an American
reader until 09:00Z, and the page said it ran to 03:59 server time. The reader
does not see a stale row; they see the deadline they were counting down to
disappear on its last day, which is the silent drop this codebase treats as the
dangerous failure.

latestBoundaryMs answers clockFor's question for the last region rather than
one reader's, so a row is history only once it is history everywhere. It follows
a game's own server map and reset hour for the same reason clockFor does —
Endfield and Reverse: 1999 both move. Nothing stored changes: this is one
comparison, not a resolved boundary written into the feed, and no expected.json
moves.

Being generous by nine hours costs an expired row at the bottom of a list.
Being strict costs a live one.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

test/time.test.ts

@@ -8,6 +8,7 @@ import {
   endingSoonestFirst,
   formatRemaining,
   HOUR,
+  latestBoundaryMs,
   urgency,
 } from "../src/shared/time.ts";
 
@@ -232,3 +233,46 @@ describe("dayStartMs", () => {
     }
   });
 });
+
+describe("latestBoundaryMs", () => {
+  /**
+   * The ingest half of the rule above. `clockFor` resolves a day-precision
+   * boundary per reader; a parser deciding whether a row is still worth
+   * publishing has no reader, so it has to answer for the last of them — and
+   * before this existed it answered for none of them, comparing the stored UTC
+   * midnight placeholder against `now` and retiring rows the app still showed.
+   */
+  const DAY_END = "2026-08-19T00:00:00.000Z";
+
+  test("is the last region's reset, not UTC midnight", () => {
+    // The Americas server is the last to roll: 04:00 on UTC-5.
+    expect(latestBoundaryMs(DAY_END, "day", "genshin")).toBe(
+      Date.parse("2026-08-19T09:00:00.000Z"),
+    );
+  });
+
+  test("is never earlier than any region's own reading of the same date", () => {
+    for (const game of [undefined, "genshin", "endfield", "r1999"] as const) {
+      const latest = latestBoundaryMs(DAY_END, "day", game);
+      for (const region of ["asia", "america", "europe"] as const) {
+        expect(latest).toBeGreaterThanOrEqual(dayStartMs("2026-08-19", region, game));
+      }
+    }
+  });
+
+  test("follows a game that states its own server map or reset hour", () => {
+    // Endfield's Europe sits on the Americas machine, so no region rolls later
+    // than 09:00Z; Reverse: 1999 is one UTC-5 server rolling at 05:00.
+    expect(latestBoundaryMs(DAY_END, "day", "endfield")).toBe(
+      Date.parse("2026-08-19T09:00:00.000Z"),
+    );
+    expect(latestBoundaryMs(DAY_END, "day", "r1999")).toBe(
+      Date.parse("2026-08-19T10:00:00.000Z"),
+    );
+  });
+
+  test("leaves an exact boundary exactly where the source put it", () => {
+    const exact = "2026-08-19T10:59:59.000Z";
+    expect(latestBoundaryMs(exact, "exact", "genshin")).toBe(Date.parse(exact));
+  });
+});