feat: add pin icon to the ChannelListItemUI

[MartinCupela]

🎯 Goal

Closes REACT-961

Implement the pinned channel design: https://www.figma.com/design/Us73erK1xFNcB5EH3hyq6Y/branch/ZvOl8vBHQaujsZ6JZRChyO/Chat-SDK-Design-System?node-id=7466-367934&m=dev

[github-actions]

Size Change: +94 B (+0.01%)

Total Size: 672 kB

📦 View Changed

Filename	Size	Change
dist/cjs/index.js	267 kB	+45 B (+0.02%)
dist/css/index.css	39.3 kB	+1 B (0%)
dist/es/index.mjs	265 kB	+48 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/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 83.53%. Comparing base (76228d8) to head (0822100).
⚠️ Report is 4 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3163      +/-   ##
==========================================
- Coverage   83.53%   83.53%   -0.01%     
==========================================
  Files         434      434              
  Lines       12928    12927       -1     
  Branches     4161     4159       -2     
==========================================
- Hits        10800    10799       -1     
  Misses       2128     2128              

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