This commit raises the minimum Coroutines version supported
to 1.4.0-M1 and above, and changes usages of awaitFirst() or
awaitFirstOrNull() to awaitSingle() or awaitSingleOrNull()
to fix gh-25007.
Closes gh-25914
Closes gh-25007
This commit introduces support for R2DBC ("Reactive Relational Database
Connectivity") with custom ConnectionFactory implementations, a
functional DatabaseClient for SQL execution, transaction management, a
bind marker abstraction database initialization utilities, and
exception translation.
Closes gh-25065