(Use converter to) restore support for Safari

[elvey]

I see from issue #25 (pubpeer.com/extensions links to https://apps.apple.com/us/app/pubpeer/id1489865828?ls=1&mt=12 ) that there was a Safari plugin. I see from https://evilmartians.com/chronicles/how-to-quickly-and-weightlessly-convert-chrome-extensions-to-safari that "With version 12, XCode introduced the Safari Web Extension Converter which gives us the ability to convert Chrome extensions to Safari extensions" "quickly and weightlessly."

I am skeptical it makes it easy but thought it was worth mentioning.

[dmicklem]

I was able to make a Safari extension that appears to work OK very easily with some minor help from Claude/Gemini. Even though I am essentially a complete novice.

Summary

I converted the Chrome extension codebase for Safari using Xcode's safari-web-extension-converter. I resolved a few configuration issues and verified that the extension works on PubMed.

xcrun safari-web-extension-converter . \ --bundle-identifier com.pubpeer.extension \ --swift

Changes / Fixes Made

• Updated macOS Deployment Target to 11.0 in Xcode to support arm64.
• Disabled preview dylib generation in Xcode to fix linker (Ld) build errors.
• Removed the empty "content_security_policy": {} entry in manifest.json which caused Safari to throw an invalid entry error under Manifest V3.

Testing

Tested on Safari (macOS). Upon granting website permissions for PubMed, PubPeer flags loaded as expected.

I am happy to provide any help I can in setting up an official Safari release!