Update open-source macOS app (Paintbrush, Objective-C/Cocoa) for macOS Tahoe compatibility

We are seeking an experienced macOS developer to modernize Paintbrush (https://paintbrush.sourceforge.io/), a free, open-source image editor for macOS written in Objective-C/Cocoa. Our team relies on Paintbrush daily, but the app has not been updated since 2021, and we are unable to upgrade beyond macOS Sequoia until it runs reliably on macOS Tahoe and later. Over the past several months we have made repeated attempts to reach the original developer (Soggy Waffles), including offers of paid support, without success. This work is funded by our company, and the updated app will remain free and open source for the wider Paintbrush community. Scope of work: * Update the existing Objective-C/Cocoa codebase to build and run reliably on macOS Tahoe, and leave it maintainable for future macOS releases. * Fix a paste bug: pasting a new image on top of an existing image cuts off the pasted image. * Fix text-tool issues: font size changes do not apply correctly, and font editing overall is unstable. The ideal candidate has solid experience with Objective-C, AppKit/Cocoa, and Xcode, and is comfortable working within an existing open-source codebase. Please include examples of relevant macOS app work in your proposal.