audio fix:

[ikreymer]

• migrate latest version of browser_controller.js from shepherd to frontend
• trigger audio init on first click to avoid browser autoplay block

[codecov]

Codecov Report

Merging #593 into develop will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop     #593   +/-   ##
========================================
  Coverage    74.31%   74.31%           
========================================
  Files           61       61           
  Lines         7402     7402           
  Branches      1129     1129           
========================================
  Hits          5501     5501           
  Misses        1531     1531           
  Partials       370      370

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