Fix in-process Execution API secrets routing in client contexts

[henry3260]

Why

Execution API requests can run inside in-process paths where SUPERVISOR_COMMS is present, which may incorrectly classify server-side code as client-side Task SDK execution.
When thathappens, Variable or Connectionreads can route back into Task SDK paths instead of staying server-side, creating a recursive chain and potential hangs.
The previous context signal was primarily environment-based, which is not always safe for request-scoped behavior in threaded in-process execution.

Because of that, Variable and Connection operations triggered while serving in-process Execution API
requests could still be routed back through Task SDK APIs instead of using the server-side secrets/backend
path, leading to recursive self-calls and hanging lookups.
closes: #65482

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[henry3260]

Could someone please take a look at this PR when they have a chance? Thanks!

[jason810496]

Nice! Thanks for the fix.

Additionally, could we add test for the scenario mentioned in the issue (#65482) to make sure the expected behavior?

Thanks.

[jason810496]

It doesn't seem like a good place for these utilities. Shouldn't models/* be something related to "Data Model" (or a Table in Metadata DB more specific).

[henry3260]

It doesn't seem like a good place for these utilities. Shouldn't models/* be something related to "Data Model" (or a Table in Metadata DB more specific).

Good point on the directory structure. I'm also concerned that models/ isn't the right fit since these aren't DB models. Where would you suggest moving them? I previously thought about utils/, but the CI checks didn't allow that, and putting them in _shared might be overkill.