add minimum validation for tilegrid size in terminalio.Terminal

[FoamyGuy]

Attempts to resolve #7885

This PR adds minimum size validation that enforces the TileGrid being no smaller than 2x2, which is arguably still too small to be practically useful. Perhaps a higher limit would be appropriate?

If there is a desire to allow 1xN sized TileGrids the logic in this will have to get reworked.

Also something for consideration would be adding an example to the docs of terminalio module that illustrate how to use it. As noted in the issue there isn't currently any sample code for it anywhere that I'm aware of.

[FoamyGuy]

I'm not sure what happened in the failed actions build. It seems to have failed on something related to submodules, but I'm not sure what specific action it was taking at the time. I did test a build of openbook_m4 locally and was able to get successful build though.

[dhalbert]

I'm not sure what happened in the failed actions build. It seems to have failed on something related to submodules, but I'm not sure what specific action it was taking at the time. I did test a build of openbook_m4 locally and was able to get successful build though.

This looks like a transient CI failure. I will start a re-run of just the failed job.

[tannewt]

This looks good to me. The main purpose is to prevent misunderstandings of what terminal needs.