Edit/Chat: Always expand to the nearest enclosing function, if available, before folding ranges

[umpox]

Description

This PR:

• Adds Tree-sitter querys for getEnclosingFunction in languages: JS/TS/Go/Python
• Updates getSmartSelection to run this query first, before using the folding range logic.

Test plan

1. Start an edit, using just a cursor position.
2. Check that the edit is correctly expanded to the nearest function.

An example of where this is a significant improvement, is in JS test files that use describe and it blocks.

• Try putting cursor inside an it block and starting an edit
• Notice that the range only expands to the entire it now, whereas before it would expand to the full describe

[dominiccooney]

NICE! 🎉