fix: prevent messages being squashed in narrow message lists

[MartinCupela]

🎯 Goal

Closes REACT-965

Also fixes:

1. images being squashed in ModalGallery component used to show multiple messages in message bubble.
2. ModalGallery background to match the underlying message bubble background.
3. ModalGallery images border radii corresponding the Figma designs

[github-actions]

Size Change: +43 B (+0.01%)

Total Size: 672 kB

📦 View Changed

Filename	Size	Change
dist/css/index.css	39.4 kB	+43 B (+0.11%)

ℹ️ View Unchanged

Filename	Size
dist/cjs/audioProcessing.js	1.32 kB
dist/cjs/emojis.js	3.01 kB
dist/cjs/index.js	267 kB
dist/cjs/mp3-encoder.js	1.27 kB
dist/cjs/useNotificationApi.js	45.4 kB
dist/css/emoji-picker.css	178 B
dist/css/emoji-replacement.css	456 B
dist/es/audioProcessing.mjs	1.31 kB
dist/es/emojis.mjs	2.52 kB
dist/es/index.mjs	265 kB
dist/es/mp3-encoder.mjs	756 B
dist/es/useNotificationApi.mjs	45.2 kB

_{compressed-size-action}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.53%. Comparing base (ead6cb5) to head (4f08dad).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3153   +/-   ##
=======================================
  Coverage   83.53%   83.53%           
=======================================
  Files         434      434           
  Lines       12926    12926           
  Branches     4159     4159           
=======================================
  Hits        10798    10798           
  Misses       2128     2128           

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[arnautov-anton]

I think this PR breaks message reactions positioning.