COND_InitialOnly functionality is limited

[m-samiec]

Description

The COND_InitialOnly replication condition support is not enabled by default, and has caveats when enabled. We recommend you don't use it where possible.

When SpatialGDKSettings::bEnableInitialOnlyReplicationCondition is disabled, all COND_InitialOnly properties will be replicated as if they were defined with COND_None.

When SpatialGDKSettings::bEnableInitialOnlyReplicationCondition is enabled, initial only data on dynamic components will not be replicated and will result in a runtime warning. Additionally, initial only data may not be consistent with the data on the rest of the actor. For instance if all data is written on an actor in epoch 1, and then again in epoch 2, it's possible for a client on checkout to receive epoch 1 of initial only data, but epoch 2 of the rest of the actor's data.