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: +326 B (+0.05%)

Total Size: 673 kB

📦 View Changed

Filename	Size	Change
dist/cjs/index.js	267 kB	+37 B (+0.01%)
dist/css/index.css	39.6 kB	+253 B (+0.64%)
dist/es/index.mjs	265 kB	+36 B (+0.01%)

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/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/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 83.59%. Comparing base (88ef71e) to head (baaad3d).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3153   +/-   ##
=======================================
  Coverage   83.59%   83.59%           
=======================================
  Files         434      434           
  Lines       12932    12934    +2     
  Branches     4163     4164    +1     
=======================================
+ Hits        10810    10812    +2     
  Misses       2122     2122           

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[arnautov-anton]

I think this PR breaks message reactions positioning.