Transaction not rolled back on early return in UpdateRecipeWithHistoryEntry

[windoze95]

Description

In internal/repository/recipe.go:238-256, a database transaction is started with tx := r.DB.Begin() on line 238. However, if the early-exit condition on lines 255-256 is hit (new active entry equals the current one), the function returns nil without calling either tx.Commit() or tx.Rollback(). This transaction is leaked — it holds a database connection until a server-side timeout fires.

Impact

• Database connection pool exhaustion under load (many small updates hitting the no-op path)
• Potential lock contention if the transaction holds any row locks before the early return

Suggested Fix

Add a deferred rollback at the top of the function, which is a no-op if the transaction was already committed:

tx := r.DB.Begin()
if tx.Error != nil {
    return tx.Error
}
defer func() {
    if r := recover(); r != nil {
        tx.Rollback()
    }
}()
// Or simply: defer tx.Rollback() — GORM's Rollback is a no-op after Commit

Then replace the early return nil on line 256 with:

tx.Rollback()
return nil

Note: This is distinct from #33 (which tracks the missing tx.Error check after Begin()) and #22 (nil pointer panic in the same function).