feat(meta): Send SDK source data

[lobsterkatie]

NOTE: This is currently not fully working because right now only pre-ordained fields come through in the sdk object (relay just drops everything else). The procedures for getting new data to be accepted by relay, and for making sure that data is queryable are WIPs. Until that's figured out, this will stay in draft status.

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We wonder sometimes how many people use our SDK via CDN, npm, and as a lambda layer. This adds it to the build so it can be hardcoded into the bundle/package. It also then includes that value in the sdk field for events.

Ref: #6256

[github-actions]

size-limit report 📦

Path	Size
@sentry/browser - ES5 CDN Bundle (gzipped + minified)	19.52 KB (+0.12% 🔺)
@sentry/browser - ES5 CDN Bundle (minified)	60.38 KB (+0.08% 🔺)
@sentry/browser - ES6 CDN Bundle (gzipped + minified)	18.18 KB (+0.14% 🔺)
@sentry/browser - ES6 CDN Bundle (minified)	53.73 KB (+0.07% 🔺)
@sentry/browser - Webpack (gzipped + minified)	19.91 KB (+0.09% 🔺)
@sentry/browser - Webpack (minified)	65.14 KB (+0.07% 🔺)
@sentry/react - Webpack (gzipped + minified)	19.93 KB (+0.1% 🔺)
@sentry/nextjs Client - Webpack (gzipped + minified)	45.9 KB (+0.05% 🔺)
@sentry/browser + @sentry/tracing - ES5 CDN Bundle (gzipped + minified)	26.34 KB (+0.08% 🔺)
@sentry/browser + @sentry/tracing - ES6 CDN Bundle (gzipped + minified)	24.75 KB (+0.1% 🔺)

[AbhiPrasad]

Hey @lobsterkatie, could we create a tracking issue for this so we can also have a place to link the eventually server-side work that needs to be done here? (I assume we PR changes to Relay also to make this work)

Looking at https://github.com/getsentry/relay/blob/c2e666d1728a2882b82e70fdbb02192c4cb0b50a/relay-general/src/protocol/clientsdk.rs#L62, we can send arbitrary information in the SDK section and it'll be forwards compatible. That means we can ship the SDK changes before it lands in Relay if this needs to be the case.

[lobsterkatie]

Hey @lobsterkatie, could we create a tracking issue for this so we can also have a place to link the eventually server-side work that needs to be done here? (I assume we PR changes to Relay also to make this work)

Done, and referenced in the PR description.

Looking at getsentry/relay@c2e666d/relay-general/src/protocol/clientsdk.rs#L62, we can send arbitrary information in the SDK section and it'll be forwards compatible. That means we can ship the SDK changes before it lands in Relay if this needs to be the case.

Yup, I've tested it. You can send it fine, but it doesn't show up in the eventual event JSON.