fix: add integration guide md file to help AI assistant's work

[szuperaz]

🎯 Goal

Improve the experience for integrators who use AI code assistents, this PR specifically helps with very vague commands like "integrate stream-chat-react"

🛠 Implementation details

Provide a description of the implementation

🎨 UI Changes

Add relevant screenshots

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 80.00%. Comparing base (d4501bd) to head (8441f5b).
⚠️ Report is 2 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2911      +/-   ##
==========================================
- Coverage   80.04%   80.00%   -0.04%     
==========================================
  Files         506      506              
  Lines       10777    10777              
  Branches     2709     2709              
==========================================
- Hits         8626     8622       -4     
- Misses       1898     1902       +4     
  Partials      253      253              

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[github-actions]

Size Change: 0 B

Total Size: 284 kB

ℹ️ View Unchanged

Filename	Size
./dist/audioProcessing-BbOs2wMd.js	1.32 kB
./dist/Channel-pqo4jV1s.js	24.4 kB
./dist/ChannelPreview-BNyNO58P.js	17.8 kB
./dist/cjs/emojis.js	3.29 kB
./dist/cjs/experimental.js	5.8 kB
./dist/cjs/index.js	165 kB
./dist/cjs/mp3-encoder.js	1.27 kB
./dist/css/index.css	104 B
./dist/css/v2/emoji-mart.css	1.84 kB
./dist/css/v2/emoji-replacement.css	300 B
./dist/css/v2/index.css	39.4 kB
./dist/css/v2/index.layout.css	22.8 kB
./dist/MessageInputContext-Buw2XInb.js	314 B

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