runapptests.js: Workaround for incomplete emulator reset

[halemmerich]

This works around the incomplete reset in emu.factoryReset() by a full re-init for every test run.

I have poked around in the emulator itself, but could not get it working correctly. This is a bit slower than it was, but at least the Uncaught SyntaxError: Got [ERASED] expected EOF errors seem to be gone for now. I think it is somehow related to the internal state of Storage that does not get fully reset on factory reset.

The tests do not run in this repo because no apps changed, but you can have a look at the actions output here: https://github.com/halemmerich/BangleApps/actions/runs/27714695139/job/81984461701

[bobrippling]

I'm afraid I don't know enough about the emulator - probably one for @gfwilliams

[halemmerich]

This is essentially a workaround like #4160 . It is a bit less complex by just doing a complete new initialization of the whole emulator instead of adding logic for waiting for finished commands. I think that should be fixed in the emulators reset methods to prevent internal state surviving.
For now I have removed the testindex stuff from this PR to make this easy to revert when the emulator has been fixed. At least it gets the CI tests working again.