code formatters should use words rather than symbols

[chdoc]

I recently noticed that saying "smash one plus" produces "one+" and "hammer one plus" produces "One+". These being code formatters, the expected output should probably be "oneplus" or "OnePlus", i.e. exclusively contain words.

Side note: even phrase formatters only replace punctuation symbols and not other mathematical symbols.

CC: @nriley

[AndreasArvidsson]

I think we should probably add a capture <user.text_code> or <user.text_code_identifier> that is just <user.text> with additional punctuation . and _. We can then use this capture for code formatters and also other commands.