Phase 8 (Core): stateful draft, quick-sell, objectives by ID, market listings

Draft v2 — stateful FUT-style pick sessions:
  - POST /draft/start?difficulty=<> — creates session, returns 5
    candidates for GK slot (position order: GK RB CB CB LB CDM CM CAM RW ST LW)
  - POST /draft/sessions/:id/pick { card_id } — validates candidate,
    advances to next position; on last pick grants coins+pack reward
    (avg OVR ≥84 → gold pack + 2000 coins, ≥78 → silver + 1000, else 400)
  - GET /draft/sessions/:id — session state with per-pick cards
  - POST /draft/sessions/:id/abandon — cancel without reward
  - Migration 0005_draft_sessions.sql

Quick-sell:
  - DELETE /collection/:owned_card_id — removes card, credits coins based
    on overall (85+ → 1500, 80-84 → 900, 75-79 → 600, 65-74 → 300, <65 → 150)

Objectives:
  - GET /objectives/:id — single objective with progress
  - POST /objectives/:id/claim — claim reward by URL param (complement to
    existing POST /objectives/claim body-param endpoint)

Market:
  - GET /market/my-listings — active listings posted by current club
  - DELETE /market/listings/:id — cancel a listing, returns card to collection

Tests: 9 new integration tests (37 total, all passing)

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

src/routes/cards.rs

@@ -12,6 +12,15 @@ use crate::{
     services::{club as club_svc, profile as profile_svc},
 };
 
+/// Quick-sell value for a card based on overall rating.
+fn quick_sell_coins(overall: u8) -> i64 {
+    if overall >= 85 { 1500 }
+    else if overall >= 80 { 900 }
+    else if overall >= 75 { 600 }
+    else if overall >= 65 { 300 }
+    else { 150 }
+}
+
 #[derive(Debug, Deserialize)]
 pub struct CardQuery {
     pub rarity: Option<String>,
@@ -114,3 +123,42 @@ pub async fn get_collection(State(state): State<AppState>) -> AppResult<Json<Val
         json!({ "collection": with_defs, "total": with_defs.len() }),
     ))
 }
+
+/// Quick-sell an owned card for instant coins. The card is removed from the collection.
+pub async fn delete_owned_card(
+    State(state): State<AppState>,
+    Path(owned_card_id): Path<String>,
+) -> AppResult<Json<Value>> {
+    let profile = profile_svc::get_active_profile(&state.pool).await?;
+    let club = club_svc::get_club_by_profile(&state.pool, &profile.id).await?;
+
+    let owned = sqlx::query_as::<_, OwnedCard>(
+        "SELECT id, club_id, card_id, is_loan, loan_matches_remaining, acquired_at \
+         FROM owned_cards WHERE id = ? AND club_id = ?",
+    )
+    .bind(&owned_card_id)
+    .bind(&club.id)
+    .fetch_optional(&state.pool)
+    .await?
+    .ok_or_else(|| AppError::NotFound(format!("owned card '{owned_card_id}' not found")))?;
+
+    let card = state
+        .card_db
+        .get(&owned.card_id)
+        .ok_or_else(|| AppError::NotFound(format!("card definition '{}' missing", owned.card_id)))?;
+
+    let coins = quick_sell_coins(card.overall);
+
+    sqlx::query("DELETE FROM owned_cards WHERE id = ?")
+        .bind(&owned_card_id)
+        .execute(&state.pool)
+        .await?;
+
+    club_svc::add_coins(&state.pool, &club.id, coins).await?;
+
+    Ok(Json(json!({
+        "quick_sold": owned_card_id,
+        "card_id": owned.card_id,
+        "coins_received": coins,
+    })))
+}