feat: add Arknights: Endfield support

Add `endfield` (Arknights: Endfield) to the registry as another
OpenGachaCodes-only, non-HoYo game (empty ennead/tori slugs,
Opengacha: "endfield", in-game redemption), plus gameOrder and docs.
Same as wuwa: watching it without opengachaBaseUrl hard-fails at
startup. Verified end-to-end against a live OpenGachaCodes instance.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Author: exec-astraea

AGENTS.md

@@ -1,9 +1,9 @@
 # hoyo-codes — agent guide
 
 A small Go service that watches for new gacha **redemption codes** (Genshin
-Impact, Honkai: Star Rail, Zenless Zone Zero, Honkai Impact 3rd, and Wuthering
-Waves) and posts them to **Discord webhooks** on a cron schedule. Docker-first,
-no database, no framework.
+Impact, Honkai: Star Rail, Zenless Zone Zero, Honkai Impact 3rd, Wuthering Waves,
+and Arknights: Endfield) and posts them to **Discord webhooks** on a cron
+schedule. Docker-first, no database, no framework.
 
 Codes are pulled from up to three APIs and merged/de-duplicated, so a hiccup on
 one source doesn't cause a miss. A source is skipped for any game it doesn't
@@ -189,7 +189,7 @@ When adding a config knob: add it to `fileConf`, resolve/validate it in
   `genshin`, `hkrpg`, `nap`, `honkai3rd`. Shape: `{"codes":[{"code","rewards":"A*60;B*5"}]}`
   (active only). Rewards get normalized (`A*60;B*5` → `A ×60, B ×5`).
 - **OpenGachaCodes** — `<opengachaBaseUrl>/games/<slug>/codes`, slugs `genshin`,
-  `starrail`, `zenless`, `wuwa` (also endfield/nte, not yet in the registry).
+  `starrail`, `zenless`, `wuwa`, `endfield` (also `nte`, not yet in the registry).
   Shape: a flat array `[{"code","rewards":["Astrite x50", ...]}]` (active only).
   Self-hosted, no auth/CORS, GET-only, strict paths (no trailing slash). A `404`
   is treated as "nothing to contribute" (not a source failure). Reward quantities

README.md

@@ -1,10 +1,11 @@
 # hoyo-codes
 
 Watches for new **gacha redemption codes** (Genshin Impact, Honkai: Star Rail,
-Zenless Zone Zero, Honkai Impact 3rd, and Wuthering Waves) and posts them to
-**Discord webhooks** on a schedule. Codes come from community HoYoverse APIs plus
-an optional self-hosted [OpenGachaCodes](config.example.yaml) instance
-(`opengachaBaseUrl`) — the sole source for non-HoYo games like Wuthering Waves.
+Zenless Zone Zero, Honkai Impact 3rd, Wuthering Waves, and Arknights: Endfield)
+and posts them to **Discord webhooks** on a schedule. Codes come from community
+HoYoverse APIs plus an optional self-hosted [OpenGachaCodes](config.example.yaml)
+instance (`opengachaBaseUrl`) — the sole source for non-HoYo games like Wuthering
+Waves and Arknights: Endfield.
 
 ## Run
 

config.example.yaml

@@ -40,8 +40,10 @@ opengachaBaseUrl: "http://localhost:8413"
 # comment it out or delete it (there's no enable/disable flag). Each listed game
 # REQUIRES both a `webhook` and a `message` (startup fails otherwise). Known keys:
 #   genshin (Genshin Impact), hsr (Honkai: Star Rail), zzz (Zenless Zone Zero),
-#   honkai3rd (Honkai Impact 3rd), wuwa (Wuthering Waves)
-# `wuwa` is served ONLY by OpenGachaCodes, so it needs opengachaBaseUrl set above.
+#   honkai3rd (Honkai Impact 3rd), wuwa (Wuthering Waves),
+#   endfield (Arknights: Endfield)
+# `wuwa` and `endfield` are served ONLY by OpenGachaCodes, so they need
+# opengachaBaseUrl set above.
 games:
   genshin:
     webhook: "https://discord.com/api/webhooks/xxx/yyy"
@@ -74,3 +76,10 @@ games:
   #   webhook: "https://discord.com/api/webhooks/eee/fff"
   #   message: "<@&222222222222222222> {count} new Wuthering Waves {if-singular:code}{if-plural:codes} 🌊"
   #   username: "Wuthering Waves Codes"
+
+  # Arknights: Endfield — also OpenGachaCodes-only (needs opengachaBaseUrl),
+  # redeemed in-game (no web link).
+  # endfield:
+  #   webhook: "https://discord.com/api/webhooks/ggg/hhh"
+  #   message: "<@&333333333333333333> {count} new Arknights: Endfield {if-singular:code}{if-plural:codes}"
+  #   username: "Endfield Codes"

games.go

@@ -16,7 +16,7 @@ type Game struct {
 
 // gameOrder is the canonical iteration order (the games map is unordered, and
 // config game keys should resolve deterministically).
-var gameOrder = []string{"genshin", "hsr", "zzz", "honkai3rd", "wuwa"}
+var gameOrder = []string{"genshin", "hsr", "zzz", "honkai3rd", "wuwa", "endfield"}
 
 // games is the registry of everything we know how to watch.
 var games = map[string]Game{
@@ -68,4 +68,14 @@ var games = map[string]Game{
 		Color:     0x3AC8D4,
 		Redeem:    "", // Wuthering Waves redeems codes in-game (no public web page).
 	},
+	"endfield": {
+		Key:  "endfield",
+		Name: "Arknights: Endfield",
+		// Not a HoYoverse game — OpenGachaCodes-only, like wuwa.
+		Ennead:    "",
+		Tori:      "",
+		Opengacha: "endfield",
+		Color:     0xE8763A,
+		Redeem:    "", // Arknights: Endfield redeems codes in-game (no public web page).
+	},
 }