[WIP] feat: add experiment for AI message limit

[jimniels]

Relevant issue(s)

[insert link(s) here]

Description

Add an experiment that gives different users different AI limits and track (long-term) which number helps conversion best.

Implementation details

• Track on a team-by-team basis (so all users in team are in the same experiment)
• Use a one-way hashing function based on team UUID to get their value
  • See example in this sheet
  • This will have to live in our shared folder, as we need the function on the server and client to calculate their bucket
• Log the experiment value in mixpanel using mixpanel.register_once
  • Leep track in localStorage if we've bucketed them already, in which case skip this step
  • Event name: experiment.aiMsgLimit.{{teamUuid}}
  • Event value: a number between 1 and 30
• Turn on a dev flag that will log what your limit number is

To Test

• Create a few different teams
• Turn on the dev flag for this feature
• Ensure the limits are different for each team

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[github-actions]

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.76%. Comparing base (2160fa8) to head (552ceed).

Additional details and impacted files

@@           Coverage Diff           @@
##               qa    #3491   +/-   ##
=======================================
  Coverage   89.76%   89.76%           
=======================================
  Files         437      437           
  Lines       90097    90097           
=======================================
  Hits        80873    80873           
  Misses       9224     9224           

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