dillon1000/react

[snap][QoL] Pragma for implicit debug mode

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Implements popular feature request ✨ per feedback from a majority of snap users. 

**Add `@debug` to the first line of your `testfilter.txt` file to opt into 
implicit debug mode**, in which debug logging is enabled anytime filter mode is 
on + only one fixture file is found. 

- live edits to testfilter.txt are reflected in watch mode, so you can add / 
remove `@debug` to `testfilter.txt` in the middle of a watch session 

- I personally don't use debug mode all the time (I often a single file filtered 
+ a lot of console log traces), but it should be easy to add `@debug` to the top 
of `testfilter.txt` and leave it there forever.