Add support for ref based state-retrieval

[pringshia]

Closes #521

More details in the issue, but essentially global application state can now be retrieved imperatively via the container application using a ref. This should make integrations easier.

mp-gcs-ref-forwarding.mp4

[codecov-commenter]

Codecov Report

Merging #570 (6423cf4) into main (47c6fa5) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #570      +/-   ##
==========================================
+ Coverage   66.32%   66.34%   +0.02%     
==========================================
  Files          81       81              
  Lines        7459     7459              
==========================================
+ Hits         4947     4949       +2     
+ Misses       2512     2510       -2     

Impacted Files	Coverage Δ
...tractions/architects/channels/websocket_channel.py	80.23% <0.00%> (-1.17%)	⬇️
mephisto/operations/supervisor.py	80.80% <0.00%> (+0.66%)	⬆️

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[JackUrb]

Thanks for waiting for this review, needed to take a moment to grasp the semantics. Looks good though! Definitely will be helpful to pull the state out where necessary.