15-Feb-2026 — migrations: handle invalid Brevo API key

build 481 — commit 38608c5

Skip Brevo migrations gracefully on 401 unauthorised responses instead of throwing. Added both Brevo migrations to the pre-applied list so they are not re-run on environments that have already applied them.

Environments without a Brevo config document caused configuredBrevo() to throw when accessing .value on null, failing the migration instead of skipping it. Separated the config lookup from the main migration logic so missing config is handled gracefully.