change comment behavior to be more consistent other commands

[fidgetingbits]

Currently if you use the change comment command it will replace the entire comment including the prefix, so for example # foo in python becomes ``. This is more consistent with what should be expected of chuck, whereas `change` should leave the `# ` (although I suppose keeping the space after the comment delimiter is debatable).

I also think it's worth adding inside comment support such that given some comments like:

# A: foo
# B: bar

You could issue a command bring fin inside comment bat and you would end up with:

# A: foo
# foo

The above already works for other target scopes like inside class.

[pokey]

One problem with "change comment" excluding the # is that it will break "bring comment", because both use the content range of the target. I wonder if this is an argument for enabling those to diverge 🤔. See discussion in #1923

Easiest is to support "inside comment"