Send ReadOnlyIntent when ApplicationIntent=ReadOnly specified

[suzak]

In our production environment, we use Always On availability groups and availability group listeners. However, tiberius does not support connecting to readonly replicas, preventing us from utilizing readonly replicas.

To connect to readonly replica via availability group listener, we should specify ApplicaitonIntent=ReadOnly in connection string¹. It sets TypeFlags' fReadOnlyIntent bit².

This PR makes tiberius to support ApplicationIntent=ReadOnly.

Footnotes

1. https://learn.microsoft.com/en-us/sql/database-engine/availability-groups/windows/configure-read-only-routing-for-an-availability-group-sql-server?view=sql-server-2017 ↩

2. https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-tds/773a62b6-ee89-4c02-9e5e-344882630aac ↩

[tomhoule]

lgtm! Thank you for the PR.

[myoder020]

how does prisma create a connection using tiberius? I'm connecting to an availability group that has read only routing setup and I can connect to it using SSMS but applying the same connection string to prisma is connecting to the primary instead of the secondary replica.