What is the shelf life of dehydrated, precooked meals? I'm planning to dry precooked meals with a food dehydrator to make them non-perishable for hiking trips.

Some of the recipes I want to cook do have ground beef, chicken, or salmon in them. I want an estimated for how long they are safe if they were dried for about 24 hours at 70°C (158F).

I plan to dehydrate the meals, freeze them until I go on the trekking trip, and then have the precooked meals in my backpack for the whole duration of the two week trip.

The food during the trip will not be refrigerated, but the temperatures are likely to be between 15°C and -5°C (59F-23F).
Dehydrating food is a common practice for trekking and backpacking.  Dehydrating vastly reduces the water activity in foods, making them a less hospitable environment for bacterial activity. You'll want to use a reliable dehydrator with a variable temperature setting, as different ingredients require different temperatures and times to properly dehydrate.  I think it would be better to dehydrate your ingredients individually, then combine them into meals.  For example, Backpacker Magazine has a handy guide with some good suggestions.  Dehydrated vegetables have a very long shelf life.  From my internet research, it seems that many folks recommend consuming dehydrated meat within two weeks.  I'm not sure you want to freeze your products.  They might become moist when thawing, thus beginning the re-hydration process before you want.  This could theoretically impact safety.