fix: poster slot fade after play before playing

[luwes]

fix #823

[vercel]

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[codecov]

Codecov Report

Attention: 18 lines in your changes are missing coverage. Please review.

Comparison is base (3ea80df) 78.55% compared to head (26fc77e) 78.44%.
Report is 5 commits behind head on main.

Files	Patch %	Lines
src/js/controller.js	33.33%	18 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #824      +/-   ##
==========================================
- Coverage   78.55%   78.44%   -0.12%     
==========================================
  Files          59       59              
  Lines       11080    11104      +24     
==========================================
+ Hits         8704     8710       +6     
- Misses       2376     2394      +18     

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[vercel]

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[cjpillsbury]

Per @luwes's advice: before/after smoke tested using

• Before: https://media-chrome.mux.dev/examples/vanilla/advanced.html
• After: https://media-chrome-git-fork-luwes-fix-poster-mux.vercel.app/examples/vanilla/advanced.html

Using dev tools, disabled cache and throttled network to slow 3g. Once controls rendered, attempted to play using play button.

• Before: poster image would fade with controls
• After: poster image stays rendered until the media has loaded.
  🎉

[cjpillsbury]

🚀