prevent traces from breaking mobile app

[bergarces]

Explanation

When calling trace returns undefined, trying to catch the promise will break the app. This prevents it.

Mobile returns undefined in that callback.

References

Checklist

• I've updated the test suite for new or updated code as appropriate
• I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• I've communicated my changes to consumers by updating changelogs for packages I've changed
• I've introduced breaking changes in this PR and have prepared draft pull requests for clients and consumer packages to resolve them

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Note

Low Risk
Low risk: a small defensive change in telemetry code to tolerate TraceCallback implementations that return undefined, preventing runtime crashes without affecting asset fetching logic.

Overview
Prevents AssetsController telemetry from breaking the app by making #emitTrace tolerate trace implementations that return undefined (only calling .catch() when a promise is returned).

Updates the assets-controller changelog with a Fixed entry documenting the trace callback handling change.

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