Migrate boundedNonWhitespaceSequence to use a scope handler

[pokey]

Proposed implementation

• First run "paint"
• For each scope returned from paint, iterate scopes from surrounding pair using the following hints:

  {
     "distalPosition": endOfPaintScope,)
     "includeDescendantScopes": true,
  }

• Note that we want to use a modified surrounding pair scope handler which uses "inside" as content range
• For each such surrounding pair scope, yield a scope which is the intersection of the surrounding pair scope with the paint scope
• Yield the paint scope itself
• For iteration scope, just use a Implement fallback scope handler #1097 scope combinator which falls back from a version of surrounding pair where the domain is actually just the inside (including whitespace), falling back to "line"

Dependencies

• Migrate surroundingPair to use a scope handler #1061

Test cases to add

(using syntax proposed in #1524)

#!! scope: {type: boundedNonWhitespaceSequence}
#!! languageId: plaintext, python, typescript

    foo(bar)
#!1 ^^^^^^^^
#!2     ^^^
#!3 ********
#!4     ***

    foo(bar baz)
#!1 ^^^^^^^     
#!2     ^^^     
#!3         ^^^ 
#!4         ^^^^
#!5 ************
#!6     ******* 

    (foo)bar
#!1  ^^^
#!2 ^^^^^^^^

    foo(bar)baz
#!1 ^^^^^^^^^^^
#!2     ^^^

    foo( bar )
#!1 ^^^^
#!2      ^^^
#!3          ^

    foo(bar )
#!1 ^^^^^^^
#!2     ^^^
#!3         ^

    (  foo)bar(baz  )
#!1 ^                
#!2    ^^^           
#!3    ^^^^^^^^^^^   
#!4            ^^^   
#!5                 ^

    colors.back)ground.dark
#!1 ^^^^^^^^^^^
#!2 ^^^^^^^^^^^^^^^^^^^^^^^

    ( foo)bar
#!1 ^
#!2   ^^^
#!3   ^^^^^^^

    (( foo)bar)baz
#!1 ^^            
#!2  ^            
#!3    ^^^        
#!4    ^^^^^^^    
#!5    ^^^^^^^^^^^