* fix: make concurrent index creations idempotent
`CREATE INDEX CONCURRENTLY` may fail and leave an invalid index behind.
See:
<https://www.postgresql.org/docs/current/sql-createindex.html#SQL-CREATEINDEX-CONCURRENTLY>
Invalid indexes will NOT be used for queries, however they is also useless and
technically the migration wasn't successful. Since #8407 we detect this
situation. #8394 allows us to fix these migrations. #8434 makes sure
that we don't mess this up (esp. that the "other checksum" pragmas are
correct).
For #7897.
* fix: multi-line processing in `check_linear_migrations.sh`
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Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>
Marco Neumann