Developer mode awareness

### Description

Ability for the code to be aware if a remote instance is in developer mode, so that code edited in developer mode doesn't accidentally run in production

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[Customer link](https://app-eu1.hubspot.com/contacts/26586079/record/0-2/6568933098)

### Which customers would this be available to

None

### Have you provided an initial effort estimate for this issue?

I have provided an initial effort estimate

No files, tests, or entry points are named. Start by clarifying how a remote instance exposes developer mode and where code edited in developer mode could run in production. Done means the code can distinguish developer-mode instances and prevents that accidental production execution.

Written by the indexing model from the issue text.