refactor(db): typed query helpers, shared test FormData helper

Replace raw db.execute tuple casts with queryRows/rowsFrom/execResult/
affectedRows helpers from lib/db, drop redundant mysql2 casts on typed
query builders, and centralize per-test fakeForm into test/fake-form.
Update db mocks in tests so helpers resolve against mocked execute.

src/actions/admin-help-tickets.ts

@@ -60,9 +60,7 @@ export const liftBanFromHelpTicket = adminAction(
 		}
 
 		const result = await db.delete(Ban).where(eq(Ban.userId, ticket.userId));
-		const removed = Number(
-			(result as unknown as [{ affectedRows: number }])[0]?.affectedRows ?? 0,
-		);
+		const removed = Number(result[0]?.affectedRows ?? 0);
 
 		const now = new Date();
 		if (ticket.open) {