Introduce Addon::notify to standardize error handling for add-ons

[ryan-robeson]

Wraps calls to add-on actions with error handling so that they don't bring down the server.

Motivation

Closes #3315

Implementation

Automated Tests

Yes

[graphite-app]

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[vinistock]

Thank you for the PR! Unfortunately, I don't think this will exactly solve the problem.

Those create_..._listener methods are only factories to hook new listeners into the AST dispatching process. An add-on is more likely to raise or accidentally try to exit during the dispatch of the AST events, which is controlled by Prism::Dispatcher.

Also, we cannot have send in the main portions of the automated requests due to performance reasons (dynamic dispatch is significantly slower).

What do you think about adding another branch to our general rescue for system exit and interrupt?

In that spot, we can catch if any features or add-ons are trying to exit and log a warning with the backtrace. Additionally, this won't mess up the LSP's own exiting mechanisms because we call exit outside of the process_message method.