feat: introduce MessageUI to ComponentContext

[arnautov-anton]

🎯 Goal

Introduce MessageUI slot which should replace Message slot in the next major release.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.34%. Comparing base (7032fb0) to head (d90d848).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3140   +/-   ##
=======================================
  Coverage   82.33%   82.34%           
=======================================
  Files         419      419           
  Lines       12269    12271    +2     
  Branches     3950     3952    +2     
=======================================
+ Hits        10102    10104    +2     
  Misses       2167     2167           

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[github-actions]

Size Change: +106 B (+0.02%)

Total Size: 618 kB

📦 View Changed

Filename	Size	Change
dist/cjs/index.js	240 kB	+53 B (+0.02%)
dist/es/index.mjs	239 kB	+53 B (+0.02%)

ℹ️ View Unchanged

Filename	Size
dist/cjs/audioProcessing.js	1.32 kB
dist/cjs/emojis.js	3.01 kB
dist/cjs/mp3-encoder.js	1.27 kB
dist/cjs/WithAudioPlayback.js	44.7 kB
dist/css/emoji-picker.css	178 B
dist/css/emoji-replacement.css	456 B
dist/css/index.css	39.1 kB
dist/es/audioProcessing.mjs	1.31 kB
dist/es/emojis.mjs	2.52 kB
dist/es/mp3-encoder.mjs	756 B
dist/es/WithAudioPlayback.mjs	44.5 kB

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