feat(developer): Support full tablet keyboard + reduced phone keyboard template in touch layout editor

Per Ron Lockwood (via email):

One thing I’ve found annoying in the touch keyboard layout of Keyman developer, is that I can’t easily get a full tablet keyboard and a reduced phone keyboard. Unless I’m missing something.

I do an import from On Screen, that gives me all the letters. Now I would like to have a phone layout that has a much reduce number of keys. I add the Phone platform. I use template and select the Basic template. Great. But when I got back to my tablet it now has the reduced set of keys.

I would like the template to just apply to the platform I’m working on.

The workaround I’ve done is to copy the code for the tablet before I apply a template and then paste it back in. But this is tedious.

Follow up:

Maybe I’ve figured something out. It seems that if I pick Traditional template, I get a normal tablet layout and a phone layout with reduced number of keys. The other templates seem to change both to reduced number. Of course I’m not quite sure because I’m getting a crash when I do this every time. You should have gotten the crash report (MD: found the crash report at https://github.com/sillsdev/keyman-issues/issues/6231).