feat: Add support for vars attribute in SentryStackFrame

[limbonaut]

📜 Description

This PR adds support for vars attribute to the SentryStackFrame class. While it existed previously, it wasn’t serialized and had a String->String mapping type.

💡 Motivation and Context

These changes are necessary for the Godot SDK to capture script variables on Android. For GDScript errors, we construct a stack trace and attach variables for each frame. There is a similar setup with Sentry Native and Cocoa SDKs.

💚 How did you test it?

I've added serialization tests.

📝 Checklist

• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[github-actions]

	Messages
📖	Do not forget to update Sentry-docs with your feature once the pull request gets approved.

Generated by 🚫 dangerJS against fdb8f10

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	369.86 ms	396.39 ms	26.53 ms
Size	1.58 MiB	2.10 MiB	533.46 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
ee747ae	382.73 ms	435.41 ms	52.68 ms
ee747ae	415.92 ms	470.15 ms	54.23 ms
ee747ae	400.46 ms	423.61 ms	23.15 ms
ee747ae	554.98 ms	611.50 ms	56.52 ms
ee747ae	358.21 ms	389.41 ms	31.20 ms
3699cd5	423.60 ms	495.52 ms	71.92 ms
85d7417	347.21 ms	394.35 ms	47.15 ms
7314dbe	437.83 ms	505.64 ms	67.81 ms
ee747ae	357.79 ms	421.84 ms	64.05 ms
ee747ae	374.71 ms	455.18 ms	80.47 ms

App size

Revision	Plain	With Sentry	Diff
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB
3699cd5	1.58 MiB	2.10 MiB	533.45 KiB
85d7417	1.58 MiB	2.10 MiB	533.44 KiB
7314dbe	1.58 MiB	2.10 MiB	533.45 KiB
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB
ee747ae	1.58 MiB	2.10 MiB	530.95 KiB

Previous results on branch: feat/frame-vars

Startup times

Revision	Plain	With Sentry	Diff
5355eb0	361.81 ms	412.04 ms	50.23 ms
712d637	420.38 ms	481.23 ms	60.85 ms
0da200a	384.89 ms	414.40 ms	29.51 ms

App size

Revision	Plain	With Sentry	Diff
5355eb0	1.58 MiB	2.10 MiB	533.47 KiB
712d637	1.58 MiB	2.10 MiB	533.46 KiB
0da200a	1.58 MiB	2.10 MiB	533.46 KiB

[lcian]

Changes look good to me, however this is technically a breaking change as we're changing the return/param types on a public class.
I'll let someone else from the team give their opinion on whether this is a reasonable change or if we should look for a workaround so that this is not breaking.

[limbonaut]

Technically, it would be a breaking change if it were in use and working as expected. Seeing that it's actually not serialized, I strongly suspect that it's not being used anywhere, or otherwise you'd have it at least reported. Not sure it's worth the trouble engineering a workaround for API contract that didn't work in the first place.

[romtsn]

LGTM, let's just add a note to the changelog, but the impact should be minimal-to-none, so we should be good here.