📝 Fix propagateTraceBaggage TSDoc @defaultValue (false → true)

[yuandesu]

Motivation

The TSDoc @defaultValue for propagateTraceBaggage currently says false, but the actual default has been true since v7 (#4226 flipped the runtime default but did not update the doc comment).

This is confirmed by Datadog's own public v7 migration guide, which documents the default as true and its CORS implication:

"The propagateTraceBaggage initialization parameter defaults to true in v7... If you use distributed tracing on cross-origin requests, either set propagateTraceBaggage: false or add baggage to your Access-Control-Allow-Headers response headers: Access-Control-Allow-Headers: traceparent, tracestate, baggage"

Upgrade the RUM Browser SDK

The stale TSDoc contradicts this public documentation. Integrators who rely on the generated .d.ts / IDE autocomplete instead of reading the migration guide have no way to know the real default. This was surfaced via a customer support ticket.

Changes

One-line JSDoc fix in packages/browser-rum-core/src/domain/configuration/configuration.ts:

 /**
  * Whether to propagate user and account IDs in the baggage header of trace requests.
  *
  * @category Tracing
- * @defaultValue false
+ * @defaultValue true
  */
 propagateTraceBaggage?: boolean | undefined

No behavior change. Affects only the generated type declarations (.d.ts) shipped in future npm releases.

Test instructions

N/A, documentation-only change with no runtime behavior affected. The true default is already in effect via the existing default-resolution logic (propagateTraceBaggage: initConfiguration.propagateTraceBaggage !== false, unchanged since #4226).

Checklist

• Tested locally — n/a, doc comment only
• Tested on staging — n/a
• Added unit tests for this change. — n/a, no behavior change
• Added e2e/integration tests for this change. — n/a
• Updated documentation and/or relevant AGENTS.md file — this PR is the doc fix itself

[github-actions]

All contributors have signed the CLA ✍️ ✅
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[yuandesu]

I have read the CLA Document and I hereby sign the CLA

[BeltranBulbarellaDD]

@yuandesu thanks for the contribution. Please wait until all CI has passed and then you will be able to merge.

[datadog-datadog-prod-us1-2]

🎉 All green!

🧪 All tests passed
❄️ No new flaky tests detected

🎯 Code Coverage (details)
• Patch Coverage: 100.00%
• Overall Coverage: 77.15% (+0.00%)

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[yuandesu]

@BeltranBulbarellaDD Thank you for reviewing!
It seems I don't have the permission to merge this PR, could you please merge it?

Thanks!