Add option to disable autocomplete and automatic diagnostics

[Ben-ADFA]

Ref. 3819

Issue Checklist

• I confirm that this feature request has not been previously suggested.
• I agree to follow the project's code of conduct.
• I have checked and verified that I am using the latest version of Code on the Go from GitHub or App Dev for All.

Additional terms

• I understand that feature requests are subject to evaluation and may not be implemented immediately.
• I agree to provide additional details if needed for a clearer understanding of the requested feature.

Feature description

Due to resource consumption with large projects, the user would like the option to disable autocomplete and any diagnostics.

From Successful Person (@SuccessfulPersion) on Telegram:
https://t.me/CodeOnTheGoDiscussions/4323
"Please add the ability to turn on or off the autocomplete mechanism and automatic diagnostics"

https://t.me/CodeOnTheGoDiscussions/4339
"I have classes with more than 3000 lines

Please add support to my request"

Use Case

When working with large amounts of code

Benefits

Less resource consumption