fix(nep): truncate editor state

[tomcat323]

Problem

We introduced editorState in data instrumentation launch. The service has a requirement of 40k character limit for the text field.

Solution

Implement a check on text length. If the text length exceeds 40k characters, section 20k max characters from the left and right side of current cursor position, so the final text is always less than 40k.

validated prod endpoint inline working for files > 40k characters.
Example request id: 57bbbe65-fbe7-47fc-81c4-c65262f47ce8

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