Proposal: Add AllowDirect to NatsKVConfig

[mjacus3]

Proposed change

Add AllowDirect as an optional configuration to NatsKVConfig so that KV streams can be configured to read from leader.

Use case

NATS KV Streams cannot currently be configured with AllowDirect = false which forces users to use Direct Get (read from followers):

nats.net/src/NATS.Client.KeyValueStore/NatsKVContext.cs

Line 274 in f2fc733

AllowDirect = true,

Until nats-server has Read-after-Write consistency (issue #6557), disabling Direct Get is the ~recommended workaround (per discussion in #7281) to get more reliable reads (with the main gap still being leader changes).

Contribution

No response

[mtmk]

thanks for the proposal @mjacus3. As @MauriceVanVeen explained this is a workaround hence we can't include it in client APIs until there is an ADR change. sorry about that. cc @ripienaar