Add 3DS-CLI

[cmdada]

• Have you checked that there aren't other open pull requests for the same manifest update/change?
• Have you verified that the manifest contains valid JSON?
• Are you certain that this manifest is not designed to obtain copyrighted material or software, which you do not have permission to distribute?
• Submitting malicious software is strictly forbidden, and potentially constitutes criminal activity, punishable by law. To the best of your knowledge, is this submission clear of any malicious intent?

---

3DS-CLI boots real RISC-V Linux on the Wii. It emulates an RV32IMA machine with
a full Sv32 MMU and runs a stock Linux 6.6 kernel with a glibc userspace off the
SD card, so the result is an actual shell rather than a simulation of one: bash,
vim, nano, htop, tree, wget and dropbear, with writes going straight to the
filesystem image on the card.

The top of the screen is an ANSI terminal (24-bit colour, scrollback, zoom) and
the bottom is an on-screen keyboard you point at with the Wiimote. A GameCube
controller works too, and the d-pad walks the key grid where neither is
convenient.

It started on the 3DS, which is where the name comes from, and this release
ports it to the Wii, Wii U, Switch and GameCube from one shared core.

Notes for review:

• supported_platforms is wii and vwii only, deliberately. Wii Mini has no
  SD card slot, and the root filesystem is ~200MB, so it cannot work there.
• The archive is apps/3ds-cli/{boot.dol,meta.xml,icon.png} plus Image at the
  root. Image is the guest kernel with the root filesystem bundled inside it;
  the app unpacks it to rootfs.ext2 on first boot and uses that writable copy
  from then on. That is why the download is large.
• Everything is GPL-3.0 and built from source in the repository's CI, including
  the Linux image: https://github.com/cmdada/3DS-CLI