rtx is an amazing tool, thank you for it!

The configuration instructions emitted by the installation script for configuring zsh don't work as written if you don't have ZDOTDIR set. I think this is a regression that was introduced recently by the changes in #963, which added the quotes, presumably to accommodate the case where ZDOTDIR includes spaces or other shell special characters.

Here's what the instructions currently look like when you install for zsh:

rtx: installing rtx...
rtx: installed successfully to /Users/ben/.local/share/rtx/bin/rtx
rtx: run the following to activate rtx in your shell:
echo "eval \"\$(/Users/ben/.local/share/rtx/bin/rtx activate zsh)\"" >> "~/.zshrc"

rtx: this must be run in order to use rtx in the terminal
rtx: run `rtx doctor` to verify this is setup correctly

Trying to run this line:

echo "eval \"\$(/Users/ben/.local/share/rtx/bin/rtx activate zsh)\"" >> "~/.zshrc"

... results in this:

zsh: no such file or directory: ~/.zshrc

... because of the fact that ~ doesn't get expanded within double-quotes. The zsh manual says:

If ZDOTDIR is unset, HOME is used instead.

... so this change falls back to $HOME in the case where $ZDOTDIR is unset.