Add Domain Field

Adding a domain field

The trap: #[serde(default)] makes old saves load, but it does nothing for SQLite. The repositories in src-tauri/crates/db/src/repositories/ use hand-written positional SQL, so a field that isn't in the column lists is silently dropped on every save/load round trip — with no error, no warning, and a passing test suite.

Start with /write-tests: name the GWT scenarios and write the test cases first. Include a non-default SQL round-trip via a fresh reader and an old-save fixture with the new serialized field absent. Typed-field tests may need the field declaration and minimal constructor/struct-literal updates to compile; add only that scaffolding before observing RED. A compile error is not behavioural evidence. Observe the old-save incompatibility before adding its serde default, and the SQL round-trip failure before persistence and migration support. If existing serde behaviour already supplies the intended default, label that passing test characterization; do not invent a failure. Then complete all six steps below, including the required serde default before committing.

1. The domain type

src-tauri/crates/domain/src/ — team.rs, player.rs, staff.rs, manager.rs, league.rs, …

pub struct Team {
    // …
    #[serde(default)]
    pub youth_budget: i64,
}

Use #[serde(default = "default_youth_budget")] with a function when zero, empty, or None is the wrong value for an old save. Think about what a save written before this feature existed should look like once loaded — that is what the default has to produce.

Domain types may hold data, constructors, Default and pure value semantics. Outcome-deciding game rules and I/O belong in ofm_core; follow the root Code quality layering rules.

2. The repository — five edit sites

Take Team as the worked example; team_repo.rs is the reference for the rest. Open src-tauri/crates/db/src/repositories/team_repo.rs and edit all five:

1. save_team's INSERT OR REPLACE INTO teams (…) column list — add the column.

2. Its VALUES (?1, ?2, …, ?N) run — add one more placeholder. The count must match the column list exactly or the insert fails at runtime.

3. The params![…] list — add the value, in the same position as the column.

4. row_to_team's positional mapping — row.get(N)?. Appending at the end is safest; inserting in the middle shifts every index after it, and nothing will tell you if you miss one.

5. Both SELECT column lists — load_all_teams and load_team. Two separate strings that must stay in sync. For a column added by a migration, wrap it as COALESCE(youth_budget, <default>) so rows written before the migration read back as the default — the existing JSON columns (media_json, player_roles_json, …) show the pattern.

   <default> must be the same value your serde default produces. These are two independent fallbacks for the same field: serde covers a save loaded from JSON, COALESCE covers a row written before the migration. If step 1 used #[serde(default = "default_youth_budget")] returning 500_000, then COALESCE(youth_budget, 0) makes the same save load differently depending on which path it came through. Either match the two, or give the column a non-null SQL DEFAULT in the migration and drop the COALESCE.

Other repositories in that directory (player_repo.rs, staff_repo.rs, competition_repo.rs, …) follow the same five-site shape.