fix(game8): drop the Battle Pass label Fandom does not print

Game8 heads Genshin's pass "Battle Pass - Moontrace"; Fandom lists "Moontrace" and files the category in a column. The label minted a second id for one event, so every battle pass since the Fandom source landed has been on the calendar twice, and a reader reported it.

Both sources now mint the same id and merge fuses them by id. The two Game8 ids that moved, Frostfarer and Moontrace (the only ones git history shows ever shipped), go in RETIRED_IDS so readers' marks follow.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/SOURCES.md

@@ -809,7 +809,7 @@ note is what stops the next person re-deriving the reason it does not.
 - **Title extraction:** Display text of the caption link beneath the banner image is taken. Link `title` (parent subpage) and `img alt` (uploaded image file name) are rejected to prevent corrupting event titles and IDs.
 - **Run-date suffixes:** Recurring event run dates (`2026-09-14`) in subpage names are stripped so dates aren't duplicated.
 - **Currency:** `latestBoundaryMs` is checked for day-precision boundaries so events aren't retired before all server regions roll.
-- **Priority & IDs:** Game8 is assigned `priority: 10` while Fandom is default/0. Two live events differ slightly in naming (`To Temper Thyself and Journey Far` vs `… Cycle 5`, and `Stygian Onslaught` vs `…: Battle of the Starburst`). Game8's higher priority breaks near-match ties in `merge.ts`, ensuring existing localStorage event IDs survive and reader completion marks remain intact. Fandom contributes 11 net-new events Game8 missed, 0 date conflicts occur, and overlapping events gain corroboration bonuses.
+- **Priority & IDs:** Game8 is assigned `priority: 10` while Fandom is default/0. Two live events differ slightly in naming (`To Temper Thyself and Journey Far` vs `… Cycle 5`, and `Stygian Onslaught` vs `…: Battle of the Starburst`). Game8's higher priority breaks near-match ties in `merge.ts`, ensuring existing localStorage event IDs survive and reader completion marks remain intact. Fandom contributes 10 net-new events Game8 missed, 0 date conflicts occur, and overlapping events gain corroboration bonuses. (Recorded as 11 until 2026-10-14: one was Game8's `Battle Pass - Frostfarer` beside Fandom's `Frostfarer`, the same event under two IDs. Game8's parser now drops that label; AGENTS.md § Fandom has the rest, including the anniversary selectors, still listed twice.)
 - **336-day event:** Genshin's anniversary 5-star selection runs 336 days (`2025-10-22` → `2026-09-23`), prompting the test duration ceiling to be raised from 180 to 365 days across the test suite and ingestion specs.
 
 ## 16. hololive Dreams — the wiki lapsed (2026-10-14); nothing else can be fetched