Inconsistent value types for BigInt fields between DB vendors

[paescuj]

Depending on the DB vendor, a different value type for BigInt fields is returned. For example, for PostgreSQL it's a string (as expected) whereas for SQLite it's a number:

// PostgreSQL
"bigint": "1000"

// SQLite
"bigint": 1000

Noticed in #21957.

• In case of SQLite, it is related to Precision lost with BIGINT TryGhost/node-sqlite3#922
  • One idea might be to switch to better-sqlite3, however that might also not work at the moment due to fix: precision lost with bigint in sqlite3 knex/knex#5482
  • Alternatively, simply cast to a string on our side, as precision is already lost anyway...
• In case of MySQL/MariaDB, it's also a number (as seen in [SDK] Set correct type for filesize #21957)
  • Should be fixable by enforcing the bigNumberStrings option, see https://github.com/mysqljs/mysql?tab=readme-ov-file#connection-options
  • Alternatively, look into Replace mysql with mysql2 #19361 where it might be the default behavior
• Need to check other DB vendors

Slightly related, because it might also be inconsistent: #20615 (knex/knex#387)