feat(core): one instance-based ownership model for every kind of owned content

Core could only own players. Everything else a FUT club holds — managers, staff,
consumables, kits, badges, balls, stadiums — had no representation, so the only
way to show one to a client was to synthesise it on read. That is the failure
mode this commit exists to make impossible: read authority, write authority and
persistent ownership authority are now the same rows.

MODEL. There is deliberately NO parallel items table. A manager, a consumable, a
kit and a player are all rows in `owned_cards`, differing only by a new
game-INDEPENDENT `content_kind` (player|manager|staff|consumable|kit|badge|ball|
stadium|misc). A game adapter translates its own taxonomy — FIFA 17's
`cardsubtypeid` and resource ranges — into one of those tokens before ownership
reaches Core; no game's numerics land here. Ownership stays INSTANCE-based:
`card_id` is the definition, `id` is the instance, and two copies of one
definition remain two rows.

`quantity` is a nullable per-instance attribute, not a replacement for the
instance. The real profile settles this: its 17 consumables are instance-based
and only SOME carry a wire `amount` (observed 1,2,4,5,10,15), while two copies of
definition 5003068 exist as two distinct instances. So NULL means "not a stack"
and a positive integer is the stack size; collapsing instances into counts is
forbidden by the model.

ACTIVE DESIGNATIONS. Migration 0024's two-slot kit table becomes
`club_active_items` over the five slots that correspond exactly to the client's
recovered equipped-state vocabulary (activeBadge 100, activeHomeKit 101,
activeAwayKit 102, activeBall 103, activeStadium 104). There is no
activeLeagueLogo or activeMisc token, so those kinds correctly get no slot. The
invariants are schema-enforced rather than conventional: PK(club_id, slot) allows
at most one item per role, `owned_card_id UNIQUE` makes "the same card is both
home and away kit" unstorable, and ON DELETE CASCADE means a quick-sold or
consumed item cannot be projected back as active. 0024's trigger is preserved in
semantics — and dropped EXPLICITLY before its table, because it lives ON
`owned_cards`, so DROP TABLE would have orphaned it and broken every later
ownership transfer. It still exists because the market moves ownership by UPDATE,
which no foreign key can observe.

CONSUMABLE ACTIONS. `services/consume.rs` is one transaction primitive —
validate source ownership and kind, validate target, mutate, consume the source
exactly once, commit — guarded by `UNIQUE(profile_id, action_identity)` in
migration 0027, the same discipline as `match_completions`. It supports both
deleting the row and decrementing a stack, chosen by the caller, inside the one
transaction and the one replay guard. It deliberately contains NO category
formulas: an unreversed effect must not be invented, so callers supply the
mutation and category validation stays explicit.

`/club/kits` is replaced by slot-generic `/club/active-items`. `get_collection`
now carries `content_kind` and `quantity`, accepts a `content_kind` filter, and
— importantly — stops dropping an owned card with a missing definition silently:
the envelope reports `owned_rows`, `unresolved_items` and the offending
definition ids. That silent `filter_map` is the documented cause of a club that
looks empty while the rows are all present.

Verified against a REAL populated club, not a fixture: the production snapshot
(migration 19) is copied to a tempdir, migrated to 0024, given two kit
designations on real owned instances, then migrated to head. 1986 owned rows
survive as content_kind='player', both designations land in `club_active_items`,
no row gains a quantity, and the old table is gone. 258 tests pass, clippy clean.

src/services/squad.rs

@@ -2,7 +2,7 @@ use crate::{
     db::Pool,
     error::{AppError, AppResult},
     models::{
-        card::{CardDefinition, OwnedCard},
+        card::{CardDefinition, OwnedCard, OWNED_CARD_SELECT},
         game_ext::{GameEntityExt, OpaqueExtensionWrite},
         squad::{
             SaveSquadRequest, SlotAssignment, Squad, SquadPlayer, SquadPlayerInput, SquadReplaced,
@@ -88,14 +88,19 @@ pub async fn validate_formation(
 
     let mut gk_count = 0usize;
     for sp in &starters {
-        let owned = sqlx::query_as::<_, OwnedCard>(
-            "SELECT id, club_id, card_id, is_loan, loan_matches_remaining, acquired_at, chemistry_style, position_override, training_bonus FROM owned_cards WHERE id = ? AND club_id = ?",
-        )
+        let owned = sqlx::query_as::<_, OwnedCard>(&format!(
+            "{OWNED_CARD_SELECT} WHERE id = ? AND club_id = ?"
+        ))
         .bind(&sp.owned_card_id)
         .bind(club_id)
         .fetch_optional(pool)
         .await?
-        .ok_or_else(|| AppError::NotFound(format!("owned card {} not found or does not belong to this club", sp.owned_card_id)))?;
+        .ok_or_else(|| {
+            AppError::NotFound(format!(
+                "owned card {} not found or does not belong to this club",
+                sp.owned_card_id
+            ))
+        })?;
 
         if let Some(card) = card_db.get(&owned.card_id) {
             if card.position == "GK" {
@@ -137,13 +142,10 @@ pub async fn calculate_chemistry(
     // Load all starter card definitions (N separate queries, fine for 11 players)
     let mut player_cards: Vec<(String, CardDefinition)> = Vec::new();
     for sp in &starters {
-        let owned = sqlx::query_as::<_, OwnedCard>(
-            "SELECT id, club_id, card_id, is_loan, loan_matches_remaining, acquired_at \
-             FROM owned_cards WHERE id = ?",
-        )
-        .bind(&sp.owned_card_id)
-        .fetch_optional(pool)
-        .await?;
+        let owned = sqlx::query_as::<_, OwnedCard>(&format!("{OWNED_CARD_SELECT} WHERE id = ?"))
+            .bind(&sp.owned_card_id)
+            .fetch_optional(pool)
+            .await?;
 
         if let Some(o) = owned {
             if let Some(card) = card_db.get(&o.card_id) {
@@ -270,13 +272,13 @@ async fn replace_squad_inner(
     // though it did.
     let mut resolved: Vec<(SlotAssignmentRef, OwnedCard)> = Vec::new();
     for s in &replacement.slots {
-        let owned = sqlx::query_as::<_, OwnedCard>(
-            "SELECT id, club_id, card_id, is_loan, loan_matches_remaining, acquired_at, chemistry_style, position_override, training_bonus FROM owned_cards WHERE id = ?",
-        )
-        .bind(&s.owned_card_id)
-        .fetch_optional(pool)
-        .await?
-        .ok_or_else(|| AppError::NotFound(format!("owned card {} not found", s.owned_card_id)))?;
+        let owned = sqlx::query_as::<_, OwnedCard>(&format!("{OWNED_CARD_SELECT} WHERE id = ?"))
+            .bind(&s.owned_card_id)
+            .fetch_optional(pool)
+            .await?
+            .ok_or_else(|| {
+                AppError::NotFound(format!("owned card {} not found", s.owned_card_id))
+            })?;
 
         if owned.club_id != club_id {
             // Deliberately the same message as "not found": whether a card