Should functions serve more than one request?

The initial reason for this design was so that:

- They were completely fresh every time
- It was impossible to store state
- There was only one degree of scaling (throughput of tasks running == throughput of function calls)
- It just feels nice conceptually. task run == function call.

But, maybe this is a bit silly. The advantages of letting them be long-running is:

- They're easier to scale (less task churn, connections are queued on server side, etc)
- State can be stored if need be
- It's just less weird, really.

The issue names no files, tests, or entry points. First trace how a function container is started and how requests are routed; completion is not defined because the thread has not chosen between one-request and long-running behavior.

Written by the indexing model from the issue text.