ref(node): Refactor node source fetching into integration

[timfish]

This PR:

• Moves eventFromException and eventFromMessage into eventbuilder to match browser SDK
• Moves source context loading/addition into a ContextLines integration
• frameContextLines option gets copied to ContextLines constructor but also pulls frameContextLines from NodeOptions to avoid a breaking change.
• frameContextLines in NodeOptions marked as @deprecated so users learn about future migration

[kamilogorek]

I like this approach much better. One thing that we might try though is to go even further and move context lines to a separate integration and add it by default. I already implemented it in v7-dev branch so you can basically copy-paste (kinda) my code from here: https://github.com/getsentry/sentry-javascript/blob/v7-dev/packages/integration-node-contextlines/src/index.ts

[kamilogorek]

That's definitely a valid concern, although with a 100 items cache it should be a very minor if any performance issue. wdyt @rhcarvalho @HazAT

[github-actions]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[timfish]

I promise, I do intend to finish this when I'm back from my extended vacation.

[timfish]

@lobsterkatie maybe you can advise on these nextjs test failures?

From what I can tell, it's completely expected for captureEvent to be called before the event is rejected by the event processors.

I'm not quite sure why my changes have caused this to start failing 🤔.
My best guess is that it's because this PR removes some async'iness.

[lobsterkatie]

This is going to be a good change!

[lobsterkatie]

@lobsterkatie maybe you can advise on these nextjs test failures?

Seems like you figured it out, but LMK if you still need help!

[timfish]

Yep worked it out in the end. Thanks for the code review.

This theoretically means that a load of async can be removed from the browser/node SDKs because it was only there to cater for the node code context loading!

[AbhiPrasad]

Nice 👍. We'll need to update docs for this as well.

[AbhiPrasad]

We can only merge once we have the docs PR ready to go

[timfish]

Docs PR done 🎉🎉🎉