feat: install & update script

[gxanshu]

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Closes #47

This script helps users install Helium tarball files and update their existing version of the Helium browser.

It’s heavily inspired by the Zen Browser tarball script.

The browser is installed at $HOME/.local/helium, which is where I usually install most software—and it seems to be the common recommendation online. However, I’m happy to change the location if you prefer something else.

I’ve tested it locally and it works well. The script also includes a fallback mechanism that restores the last installed version of Helium if anything goes wrong during the update.

We can add a URL on helium website that will redirect to the Github script, just like bun did.

curl -fsSL https://bun.sh/install | bash

You can test it now — Helium can currently be installed and updated with:

curl -fsSL https://raw.githubusercontent.com/gxanshu/helium-linux/refs/heads/main/scripts/install.sh | bash

[imjulianeral]

I'd love to have this