Provide standardized additional context for Flow sessions and triggers
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## Problem
When adding new flows to be triggered by buttons or other triggers, such as assigning a service account to an issue, one of the most important parts is that the flow receives the correct context to operate, such as the issue it's supposed to operate on or the pipeline it's supposed to fix.
When allowing end-users to create their own agents and flows, it is also important that they understand how context from the point of the trigger is passed in, so that it can be used in agent/flow design.
Without standardization, there is the risk of confusion and slightly different implementation/naming.
## Desired Outcome
An agreed upon standard on what/how context is passed from the point of the trigger to a session for a flow.
issue