Register as MimeType handler

[Jacalz]

Checklist

• I have searched the issue tracker for open issues that relate to the same feature, before opening a new one.
• This issue only relates to a single feature. I will open new issues for any other features.

Is your feature request related to a problem?

There seems to be some sort of agreement around using wormhole-transfer as the scheme for wormhole sends. Our QR codes are for example currently using codes on the form of wormhole-transfer:123-example-code. We should implement support for handling the scheme and then register to the operating system that we can handle that MimeType.

We also need to make sure that we handle the URI-scheme parsing correctly (probably also relates to QR-codes partially): https://github.com/magic-wormhole/magic-wormhole-protocols/blob/01b7c46ffaec4c12866f99bb2596fd4e49db460a/uri-scheme.md?plain=1#L12

Looking at Warp, they register the MimeType field for both wormhole-transfer and warp. We might want to do the same but with the latter as rymdport.

Describe the solution you'd like to see.

It is unclear as to how this will be implemented.

Systems to implement this for:

• Linux and BSD
• macOS
• Windows

[Jacalz]

Possibly useful documentation for Linux/BSD:

• https://wiki.archlinux.org/title/XDG_MIME_Applications
• https://specifications.freedesktop.org/desktop-entry-spec/desktop-entry-spec-latest.html#exec-variables

It might just be the case that my previous attempts were unsuccessful because we use "%F" and not "%U".