feat(browser): Do not include metrics in base CDN bundle

[mydea]

Metrics are only included when performance is included, reducing the base bundle size.

We always expose a shim so there is no API breakage, it just does nothing.

I noticed this while working on #12226.

[Lms24]

I'm not opposed to the change; on the contrary - whatever helps shrinking the bytes for the base bundle.

Just wondering if it's correct to couple metrics to the performance bundles since product-wise metrics isn't strictly tied to performance 🤔 Maybe it's good enough for now though. wdyt?

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser	21.74 KB (0%)
@sentry/browser (incl. Tracing)	32.75 KB (0%)
@sentry/browser (incl. Tracing, Replay)	68.22 KB (0%)
@sentry/browser (incl. Tracing, Replay) - with treeshaking flags	61.64 KB (0%)
@sentry/browser (incl. Tracing, Replay with Canvas)	72.27 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback)	84.33 KB (0%)
@sentry/browser (incl. Tracing, Replay, Feedback, metrics)	85.8 KB (0%)
@sentry/browser (incl. metrics)	23.13 KB (0%)
@sentry/browser (incl. Feedback)	37.75 KB (0%)
@sentry/browser (incl. sendFeedback)	26.32 KB (0%)
@sentry/browser (incl. FeedbackAsync)	30.74 KB (0%)
@sentry/react	24.43 KB (0%)
@sentry/react (incl. Tracing)	35.75 KB (0%)
@sentry/vue	25.68 KB (0%)
@sentry/vue (incl. Tracing)	34.56 KB (0%)
@sentry/svelte	21.88 KB (0%)
CDN Bundle	22.96 KB (-5.44% 🔽)
CDN Bundle (incl. Tracing)	34.22 KB (+0.01% 🔺)
CDN Bundle (incl. Tracing, Replay)	68.04 KB (-0.01% 🔽)
CDN Bundle (incl. Tracing, Replay, Feedback)	73.04 KB (-0.01% 🔽)
CDN Bundle - uncompressed	67.78 KB (-5.16% 🔽)
CDN Bundle (incl. Tracing) - uncompressed	101.58 KB (0%)
CDN Bundle (incl. Tracing, Replay) - uncompressed	211.48 KB (0%)
CDN Bundle (incl. Tracing, Replay, Feedback) - uncompressed	223.86 KB (0%)
@sentry/nextjs (client)	35.1 KB (0%)
@sentry/sveltekit (client)	33.35 KB (0%)
@sentry/node	114.64 KB (-0.01% 🔽)
@sentry/aws-serverless	103.32 KB (-0.01% 🔽)

[mydea]

I'm not opposed to the change; on the contrary - whatever helps shrinking the bytes for the base bundle.

Just wondering if it's correct to couple metrics to the performance bundles since product-wise metrics isn't strictly tied to performance 🤔 Maybe it's good enough for now though. wdyt?

Yeah, I know what you mean.

IMHO we have a few options here:

1. Just leave it as this for now, is you want metrics use the performance bundle.
2. Add a new bundle with metrics (I'd not love that, because of matrix 😬 )
3. Add a pluggable integration that users can use to add metrics support - I think this would be possible to do.

Personally I'd go with 1. for now and possibly extend with 3 if we find out it's a problem/there is a need for that?

[Lms24]

Personally I'd go with 1. for now and possibly extend with 3 if we find out it's a problem/there is a need for that?

Yup, sounds fair to me!