Add exclusion character for searchString copy functionality

[gorsech]

I love the string copying functionality, but plain regex can be a bit hard to parse at a quick glance. I usually add additional strings that include some indicator of what the regex represents, or strings to separate the regex by Act. However, those can be copied as well.

I updated the feature to exclude any strings containing #. Clicking the excluded line will not copy its text or generate a toast. # is used in regex, but to my knowledge, it wouldn't apply to any usage from https://poe.re/ although another character (such as @) might be a better candidate.

Note: I am not a software dev, so there may be a better method for implementing this - please feel free to reject this PR. Happy to share this feedback as an issue if that's preferred instead, just lmk.

[HeartofPhos]

I've modified it a bit to allow for syntax highlighting and less cluttered UI in the side bar. Ideally will add dedicated inputs for search strings instead of a block of text someday, but this is a reasonable enough solution for the moment