Provide LSP Folding Range Request

[dklilley]

Is your feature request related to a problem? Please describe.
Some IDEs (such as VS Code) provide their own LSP-free solutions for code folding using the following methods:

1. Indentation - regions with the same indentation level will be folded
2. Regular Expression - can specify patterns for the start/end of folding regions.

There are problems with each of these:

1. Indentation-based folding may fail or fold incorrect regions when indentation is incorrect in the file, or when classic function indenting is used.
2. RegEx-based folding may incorrectly identify 'end' in comments and strings

Describe the solution you'd like
Provide a handler for Folding Range Requests

[dklilley]

Closing this issue - this functionality was added in v1.2.4, and requires MATLAB R2024b or later.