Cannot instal pod

santhosh@CONTUS-LAP-290 CastScreenProject % pod init

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### Command

```
/Users/santhosh/.rbenv/versions/3.3.0/bin/pod init
```

### Report

* What did you do?

* What did you expect to happen?

* What happened instead?

### Stack

```
CocoaPods : 1.15.2
Ruby : ruby 3.3.0 (2023-12-25 revision 5124f9ac75) [x86_64-darwin22]
RubyGems : 3.5.3
Host : macOS 15.0 (24A335)
Xcode : 16.0 (16A242d)
Git : git version 2.39.5 (Apple Git-154)
Ruby lib dir : /Users/santhosh/.rbenv/versions/3.3.0/lib
Repositories : trunk - CDN - https://cdn.cocoapods.org/
```

### Plugins

```
cocoapods-deintegrate : 1.0.5
cocoapods-plugins : 1.0.0
cocoapods-search : 1.0.1
cocoapods-trunk : 1.6.0
cocoapods-try : 1.2.0
```

### Error

```
RuntimeError - `PBXGroup` attempted to initialize an object with unknown ISA `PBXFileSystemSynchronizedRootGroup` from attributes: `{"isa"=>"PBXFileSystemSynchronizedRootGroup", "exceptions"=>["7F8F59DC2CB5142E001968DF"], "path"=>"CastScreenProject", "sourceTree"=>""}`
If this ISA was generated by Xcode please file an issue: https://github.com/CocoaPods/Xcodeproj/issues/new
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:359:in `rescue in object_with_uuid'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:349:in `object_with_uuid'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:300:in `block (2 levels) in configure_with_plist'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:299:in `each'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:299:in `block in configure_with_plist'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:296:in `each'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:296:in `configure_with_plist'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project.rb:272:in `new_from_plist'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:350:in `object_with_uuid'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:290:in `block in configure_with_plist'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:287:in `each'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project/object.rb:287:in `configure_with_plist'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project.rb:272:in `new_from_plist'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project.rb:213:in `initialize_from_file'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/xcodeproj-1.25.1/lib/xcodeproj/project.rb:113:in `open'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/cocoapods-1.15.2/lib/cocoapods/command/init.rb:41:in `validate!'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/claide-1.1.0/lib/claide/command.rb:333:in `run'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/cocoapods-1.15.2/lib/cocoapods/command.rb:52:in `run'
/Users/santhosh/.rbenv/versions/3.3.0/lib/ruby/gems/3.3.0/gems/cocoapods-1.15.2/bin/pod:55:in `'
/Users/santhosh/.rbenv/versions/3.3.0/bin/pod:25:in `load'
/Users/santhosh/.rbenv/versions/3.3.0/bin/pod:25:in `'
```

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[!] Oh no, an error occurred.

Search for existing GitHub issues similar to yours:
https://github.com/CocoaPods/CocoaPods/search?q=%60PBXGroup%60+attempted+to+initialize+an+object+with+unknown+ISA+%60PBXFileSystemSynchronizedRootGroup%60+from+attributes%3A+%60%7B%22isa%22%3D%3E%22PBXFileSystemSynchronizedRootGroup%22%2C+%22exceptions%22%3D%3E%5B%227F8F59DC2CB5142E001968DF%22%5D%2C+%22path%22%3D%3E%22CastScreenProject%22%2C+%22sourceTree%22%3D%3E%22%3Cgroup%3E%22%7D%60%0AIf+this+ISA+was+generated+by+Xcode+please+file+an+issue%3A+https%3A%2F%2Fgithub.com%2FCocoaPods%2FXcodeproj%2Fissues%2Fnew&type=Issues

Start with xcodeproj-1.25.1/lib/xcodeproj/project/object.rb around object_with_uuid and the CocoaPods init entry point shown in the stack trace. Reproduce pod init against the reported Xcode 16 project and trace handling of PBXFileSystemSynchronizedRootGroup. Done means the project loads without the unknown-ISA RuntimeError.

Written by the indexing model from the issue text.