Initial commit: OpenFUT Core

Offline Ultimate Team backend — game-independent REST API.

- 19 API endpoints: auth, profiles, clubs, cards, packs, squads,
  objectives, SBCs, match rewards, NPC market, statistics
- Axum + SQLite + SQLx with full migrations
- Weighted pack generator, SBC validation engine
- JSON-driven mod data (cards, packs, objectives, SBCs)
- 5 integration tests passing

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/services/club.rs

@@ -0,0 +1,71 @@
+use crate::{
+    db::Pool,
+    error::{AppError, AppResult},
+    models::club::Club,
+};
+use chrono::Utc;
+
+pub async fn get_club_by_profile(pool: &Pool, profile_id: &str) -> AppResult<Club> {
+    sqlx::query_as::<_, Club>(
+        "SELECT id, profile_id, name, coins, level, created_at, updated_at FROM clubs WHERE profile_id = ? LIMIT 1"
+    )
+    .bind(profile_id)
+    .fetch_optional(pool)
+    .await?
+    .ok_or_else(|| AppError::NotFound("club not found".into()))
+}
+
+pub async fn create_club(pool: &Pool, club: &Club) -> AppResult<()> {
+    sqlx::query(
+        "INSERT INTO clubs (id, profile_id, name, coins, level, created_at, updated_at) VALUES (?, ?, ?, ?, ?, ?, ?)"
+    )
+    .bind(&club.id)
+    .bind(&club.profile_id)
+    .bind(&club.name)
+    .bind(club.coins)
+    .bind(club.level)
+    .bind(club.created_at)
+    .bind(club.updated_at)
+    .execute(pool)
+    .await?;
+    Ok(())
+}
+
+pub async fn add_coins(pool: &Pool, club_id: &str, amount: i64) -> AppResult<i64> {
+    let now = Utc::now();
+    sqlx::query("UPDATE clubs SET coins = coins + ?, updated_at = ? WHERE id = ?")
+        .bind(amount)
+        .bind(now)
+        .bind(club_id)
+        .execute(pool)
+        .await?;
+
+    let new_balance = sqlx::query_scalar::<_, i64>("SELECT coins FROM clubs WHERE id = ?")
+        .bind(club_id)
+        .fetch_one(pool)
+        .await?;
+    Ok(new_balance)
+}
+
+pub async fn spend_coins(pool: &Pool, club_id: &str, amount: i64) -> AppResult<i64> {
+    let balance = sqlx::query_scalar::<_, i64>("SELECT coins FROM clubs WHERE id = ?")
+        .bind(club_id)
+        .fetch_one(pool)
+        .await?;
+
+    if balance < amount {
+        return Err(AppError::BadRequest(format!(
+            "insufficient coins: have {balance}, need {amount}"
+        )));
+    }
+
+    let now = Utc::now();
+    sqlx::query("UPDATE clubs SET coins = coins - ?, updated_at = ? WHERE id = ?")
+        .bind(amount)
+        .bind(now)
+        .bind(club_id)
+        .execute(pool)
+        .await?;
+
+    Ok(balance - amount)
+}