The phase 3 payment query used ORDER BY created_at DESC LIMIT 1.
Within a single transaction, NOW() returns the same timestamp for all
inserts, making the ordering non-deterministic when other parallel tests
insert payment rows with the same timestamp. Fix by parsing the
response's payment ID and querying by it directly.
Also revert eslint.config.js back to error-level rules for all categories
(removing the previous 'warn' overrides).
Refactor BuyGiftCard to insert pending payment before Square call with VAT applied. Add transaction wrapping to gift card handlers. Remove redundant Content-Type header sets. Migrate all time.Now() to clock.Now().
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Add GetVATConfig for reading VAT settings via any db.Querier, ApplyVATToBookingPayment for applying VAT to payment records, and ApplyVATToTillSale for SPV gift card till sales. Errors are logged without blocking payment flow.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>