[FERN-SCRIBE] Update readme and global header documentation #323
Description
📝 What do you want Fern Scribe (AI Technical Writer) to do?
Update readme and global header documentation. make a new page in the deep dives section for readme and link to the reference documentation
🔗 Link to existing Slack thread
https://buildwithfern.slack.com/archives/C08T7EHDHMW/p1754058964789879
📋 Do you know of any documentation that needs to be updated?
https://buildwithfern.com/learn/sdks/deep-dives/global-headers
https://buildwithfern.com/learn/sdks/reference/generators-yml
and the open api spec
❌ If yes, describe why that documentation is incorrect
No response
📰 Changelog Update Required
- Yes, include changelog entry
- No changelog needed
📎 Additional Context
No response