The main repo has some simulator code that gives you a simple REPL for testing ops and stuff, stubbing out all the hardware behavior with printf messages. I haven’t really used this and I think it basically is sort of a “live mode” simulation, so it may not be quite what you want for scripting.
The awesome VCV Rack ports of the Trilogy modules are based on swapping out IO code from libavr32, so it should be possible to do such an emulation of Teletype, but there’s definitely quite a bit of work to do there to emulate the screen and keyboard support.
To some extent you probably could do this, yeah. You would need some way to put TT in I2C follower mode for receiving text input, and I don’t yet understand how crow’s I2C packet construction works well enough to tell you what kind of modifications this might need on the crow side. Sending a ton of data over the I2C bus may also interfere with other stuff on the bus. Some interesting stuff to figure out here, and seems fairly similar to having an I2C leader supply a whole preset to some follower module, an interesting possibility.
Another thing you could probably do is use the UART header on the back of TT to establish a full-fledged terminal session with TT. Note that I have no idea if such a thing is possible with TT’s board design without a hardware mod. Currently the UART is only used for printing debug information (TT transmitting to host) but it should be possible with some firmware changes for it to also receive input, which could be wired up to evaluate TTscript like in live mode. You would still need to figure out what to do about editing scripts / patterns / etc but this seems like a pretty attractive option to me.