feat(enakgame): spin as an EnakGame game; remove the old game flow

EnakGame phase 10 of docs/tasks-enakgame.md (EG-1001 to EG-1003).

Spin (EG-1001)
- PROBABILITY entries take an optional label (a wheel segment). The customer game
  list shows a PROBABILITY game's prizes (entry, label, amount, never weights), and
  completing returns the drawn prize, so the client can draw the wheel and stop it
  on the server's draw.
- docs/enakgame-spin.md: the admin steps to set up spin per organization (no
  seeder) and the customer app flow. An HTTP test plays it end to end.

Old game flow removed (EG-1002)
- Routes POST /customer/spin, GET /customer/games, GET /customer/ferris-wheel, and
  admin /marketing/games, /marketing/game-prizes, /marketing/rewards, with their
  handlers, services, processors, repositories, validators, models, contracts,
  mappers and tests (GamePlayProcessor, SpinGameService, rewards, ...). This also
  closes RFC §15 findings 1 and 2 (double charge, spinning another org's game).
- Tables games, game_prizes, game_plays and rewards stay for ledger history.
  entities.StringSlice moves to its own file; the omset tracker (unrouted) keeps
  game_id but no longer embeds the old game response.

games.is_active dropped (EG-1003)
- Migration 000115; nothing reads metadata.coin_cost any more.

The EnakPoint integration docs now point at /customer/enakgame. The Postgres tests
were not run: no test database here. Migration 000115 has not been run anywhere.
The customer app must stop calling the removed endpoints before this is deployed.

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

docs/enakgame-spin.md

@@ -0,0 +1,86 @@
+# Spin sebagai Game EnakGame
+
+**Sumber:** [RFC EnakGame](rfc-enakgame.md) §14, task EG-1001
+**Pembaca:** admin organisasi dan tim backoffice / aplikasi customer
+
+Spin lama (`POST /customer/spin`) diganti dengan game EnakGame biasa: tipe `SPIN`,
+reward `PROBABILITY`, hadiah berupa EnakCoin. Spin dimainkan lewat endpoint session
+yang sama dengan game lain, sehingga ikut mendapat idempotency, refund otomatis, budget,
+event, dan Economy Guard.
+
+Tidak ada seeder: setiap organisasi membuat spin-nya sendiri lewat API admin di bawah.
+Semua langkah memakai token admin organisasi; langkah 2–4 butuh loyalty manager.
+
+## Langkah Admin
+
+### 1. Buat game
+
+`POST /api/v1/marketing/enakgame/games`
+
+```json
+{
+  "name": "Spin Harian",
+  "slug": "spin",
+  "type": "SPIN",
+  "entry_cost": 5,
+  "status": "ACTIVE",
+  "thumbnail_url": "https://…/spin.png",
+  "game_url": "https://…/spin/index.html"
+}
+```
+
+`entry_cost` adalah EnakCoin yang dipotong setiap kali spin (minimal 1).
+
+### 2. Buat reward config `PROBABILITY`
+
+`POST /api/v1/marketing/enakgame/games/:id/reward-configs`
+
+```json
+{
+  "reward_type": "PROBABILITY",
+  "max_reward": 50,
+  "rules": {
+    "table": [
+      { "weight": 50, "amount": 0,  "label": "Zonk" },
+      { "weight": 30, "amount": 3,  "label": "3 Coin" },
+      { "weight": 15, "amount": 10, "label": "10 Coin" },
+      { "weight": 5,  "amount": 50, "label": "Jackpot" }
+    ]
+  },
+  "reason": "Spin pertama"
+}
+```
+
+- Satu baris `table` = satu segmen roda, urut searah gambar roda.
+- `weight` bilangan bulat ≥ 1. Peluang segmen = `weight` ÷ total weight (di atas: 50%,
+  30%, 15%, 5%). Weight tidak pernah dikirim ke customer.
+- `amount` EnakCoin yang didapat (boleh 0). `label` opsional, maksimal 100 karakter,
+  ditampilkan di roda.
+- `max_reward` minimal sebesar `amount` terbesar, kalau tidak hadiah besar terpotong.
+
+### 3. Aktifkan config
+
+`POST /api/v1/marketing/enakgame/reward-configs/:id/activate`
+
+Mengganti hadiah nanti berarti membuat versi config baru lalu mengaktifkannya; session
+yang sedang berjalan tetap memakai versi saat dimulai.
+
+### 4. Pastikan ada budget global bulan berjalan
+
+`POST /api/v1/marketing/enakgame/budgets` dengan `scope: "GLOBAL"`, bila belum ada. Tanpa
+budget global, customer tidak bisa memulai game apa pun.
+
+## Alur di Aplikasi Customer
+
+1. `GET /api/v1/customer/enakgame/games`: game spin punya `prizes`, yaitu segmen roda
+   (`entry`, `label`, `amount`) dalam urutan config. Gambar roda dari sini.
+2. `POST /api/v1/customer/enakgame/sessions` dengan `{"game_id": "…"}` dan header
+   `Idempotency-Key`. Entry cost dipotong di sini.
+3. `POST /api/v1/customer/enakgame/sessions/:id/complete` dengan body `{}`. Server yang
+   mengundi. Response berisi `prize` (`entry`, `label`, `amount`): putar roda sampai
+   berhenti di segmen `entry` itu. `reward_total` adalah Coin yang benar-benar masuk,
+   bisa lebih besar dari `prize.amount` karena event, atau lebih kecil karena limit
+   harian (`limited_by`).
+
+Aplikasi tidak boleh mengundi sendiri atau mengirim hadiah: apa pun yang dikirim selain
+data hasil diabaikan.