Properly type wrapTransaction in domains/alert/src/common/db.ts (drop @ts-expect-error)

From DeepSource sweep 2026-05-14 (see memory/2026-05-14-deepsource-sweep-domains-alert.md, Tier-1 Finding #3). Current code (src/common/db.ts:34-37): ```typescript // @ts-expect-error Parameter '_' implicitly has an 'any' type. export function wrapTransaction<T>(tx: PrismaClientTx | undefined, fn: (_) => Promise<T>) { return tx ? fn(tx) : prisma.$transaction(fn); } ``` The @ts-expect-error papers over an untyped `fn` parameter. The correct type (`PrismaClientTx`) is defined two lines above. Fix: ```typescript export function wrapTransaction<T>( tx: PrismaClientTx | undefined, fn: (tx: PrismaClientTx) => Promise<T>, ) { return tx ? fn(tx) : prisma.$transaction(fn); } ``` Single caller is src/repositories/alert/storeAlerts.ts:114, which already passes `async (tx) => { ... }` — should infer fine. If `prisma.$transaction` rejects the narrowed `fn`, widen to `(tx: PrismaClientTx | Prisma.TransactionClient) => Promise<T>` or type-narrow at the call site. Either way, no @ts-expect-error needed. DoD: PR opened, `yarn tsc --noEmit` passes in domains/alert, jest tests still green, CODEOWNER-approved, merged.