Clarify multimodal experiment coordination/correlation/metadata in diagrams

From Alex Piet:

> This architecture assumes that modalities that are recorded simultaneously (behavior + physiology, for example) will be processed separately and then later combined. Combining the metadata requires that certain fields in each modalities' metadata match. See this issue for more details: https://github.com/AllenNeuralDynamics/aind-software-docs/issues/174
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> Coordinating metadata means that the acquisition software must be coordinated. This either means a human must manually enter information in each modalities' software, or there is an orchestration layer that coordinates this information. There has been a lot of hand-waving about how this will work, but no details. I would like the plan for how this will be coordinated documented in this diagram

I think the generic diagrams shouldn't try to capture this, but it might be useful to provide some extra diagrams to show how this would work. I think the specific question involves the lab management system <-> lab interface, which at the moment is fairly ill-defined, but we've had discussions about something like a session token server.