Restore reliable uv/Tk macOS packaging and double-click installation #47

Problem

The current main refactor removed the earlier macOS app-bundle/Tk bootstrap work:

• cdisplayagain-macos.spec was deleted.
• tk_bootstrap.py was deleted.
• pyproject.toml no longer prefers uv-managed Python.
• Makefile deploy now builds a plain one-file executable.
• macOS install-desktop only prints instructions; it does not register .cbz/.cbr with Launch Services.
• README setup reverted to brew install python-tk.

This risks bringing back the original macOS failure where uv-managed Python has _tkinter but cannot locate Tcl/Tk runtime files. It also means a clean macOS checkout cannot reliably provide double-click opening through the documented one-command deployment.

Fix

Choose and document one supported macOS distribution path:

1. Build a real .app bundle with Tcl/Tk resources, the existing icon, CBZ/CBR document declarations, and a stable bundle identifier; or
2. Explicitly require a system Python/packaged runtime and provide a tested Launch Services registration command.

The preferred path should remain compatible with the project’s uv-first setup and should not silently depend on a developer’s working directory or manually installed Python packages.

Tests/manual verification

• Run the documented setup on a clean macOS environment.
• Launch a CBZ and CBR by Finder double-click.
• Launch a file whose path contains spaces and Unicode.
• Launch when the app is already running.
• Verify the existing cdisplayagain icon appears.
• Verify the app logs to a writable user directory.
• Inspect the final bundle’s Info.plist and confirm CBZ/CBR document declarations.

Done criteria

• A fresh macOS install can follow the README and open CBZ/CBR files by double-click.
• No brew install python-tk workaround is required if uv-managed Python is the supported path.
• Launch Services registration is repeatable and documented.
• CLI launching still works.