Can a tenure-track job candidate infer any meaning from the response to an initial contact email?

Don't stress out about the responses, since it's nearly impossible to get reliable information by reading between the lines. The variation in how people might respond is enormous, and unless you really know the people involved it's hard to know what it means. For example, suppose someone sends a friendly, encouraging reply. Maybe it means you have a real shot at the job. Maybe it means they think you have a real shot, but they could be totally wrong. (Sometimes people on hiring committees have unrealistic beliefs about how everything will play out.) Maybe it's just their personality and has nothing to do with your chances. Maybe they are deliberately saying the same thing to everyone in order to avoid awkwardness. If you don't know them pretty well, all you can do is guess. Of course a standoffish reply is equally difficult to interpret. The net effect is that you'll get replies that look like they may contain information, but you really won't know what, if anything, they mean. It's best to resign yourself to this now, rather than spending a lot of time worrying over how to interpret replies and not actually learning anything valuable in the process.

There is probably a small positive correlation between how encouraging e-mail responses are and how much of a chance you have. But there is also a large amount of random chance, depending on the personality of the responder. It can be maddening, and it is probably useless, to try to extract the signal from the noise.

Usually if you get specific information right away, it will be bad news. In particular, if your research interests are not a good match for whatever the search committee is looking for, you might be told immediately. Otherwise, I wouldn't recommend trying to read too much into the content (or presence or absence of these e-mails).

Good luck on your job search!

A few years ago, fresh out of PhD, I was hunting for a university job. I applied to a bunch of universities ranging from world's top to average/below average. I knew I didn't have a faintest chance to get a job at prestigious university, but I really enjoyed reading their responses:

Despite your excellent qualification, we regret to inform you that we hired another person, who was more suitable for this position...

Reading that would make me happy. They think I have an "excellent qualification"!

I think 99% of negative responses are standard and professionally tailored to incite positive emotions in spite of bad news. Like firing someone of Friday before Christmas.

All the positive responses I ever received/sent were as dry as they can get, loaded with specific and technical info.

With that being said, job hunting is a tremendously time consuming activity, like a full-time job. Trying to infer something from non-explicitly positive responses seems to be a waste of precious time. If the response seems neutral/unclear and you need to decide whether to agree to another job or not, then you should immediately ask them to clarify their response saying that you have a decision to make.