It's all defined in laws. Here's California as an example
where you are getting your opinion on violence from
Non-injury (not just physical). More ancient precept. With the exception of trolling online for a very specific purpose, I hold to that as best as I can manage. I fail. A lot. Doesn't mean I don't try.
I think the rest of your questions can be answered through the lens of non-injury.
right to not be impeded in public is coming from
Well, first, non-inury. Does it cause a loss of income or business either to a business or a private citizen? If it does, it's not peaceful because that's a form of injury which you can seek legal recourse.
Second, very specifically:
Examples of laws which limit freedom of assembly are found in various riot acts, unlawful assembly laws, and ordinances prohibiting the blocking of sidewalks.
the first amendment pretty well allows them to sit in the middle of a street or whatever rankles you so.
Absolutely wrong.
https://www.lawyers.com/legal-info/criminal/the-right-to-gather-has-some-restrictions.html
Police routinely arrest protestors who block traffic in freeways or bridges. That’s generally allowed, because maintaining public safety involves keeping streets open and traffic moving.
another person cant waste it.
I absolutely can waste your time. Easily. I can destroy uninsured property you own. I can damage something difficult to replace that you must have. To replace it, you must spend time looking for it and then, since you trade your time for money, waste even more "time" buy purchasing it. I can hide something of yours or on your property (maybe spill a bunch of oil or antifreeze in your yard) causing you to look for it.
It is extremely easy to waste another person's time.
only a government official has the authority to waste someone's time
Theft of something which cannot be replaced is not appropriate in any way.
im still not sure where you are getting your opinion on violence from. to my knowledge only certain kinds of harrassment would be considered violent and thats any that implies a threat of physical aggression. i guess by your example you might also consider trump's refusal to acknowledge obama as a US citizen violent harassment and terrorism. i'm curious where you draw the line between free speech and terrorism. i also dont get where this right to not be impeded in public is coming from. as long as a protest isnt threatening in nature the first amendment pretty well allows them to sit in the middle of a street or whatever rankles you so.
one only wastes their own time, another person cant waste it.
*i should amend that last statement to add that only a government official has the authority to waste someone's time.