feat(baggage): Added double baggage prevention logic

[harshit078]

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Closes #19158

[Lms24]

Hey @harshit078 thanks for taking over the issue and opening the PR! I see there are some tests failing regarding the mergeBaggageHeaders function. Are you aware of this and looking into fixing it or should we take over? Just let me know :)

There's one test named "overwrites existing Sentry entries with new ones", so I'm wondering why we'd end up with duplicated entries. This might be related to #17355 which got merged yesterday.

[harshit078]

Hey @Lms24 , yes I am resolving the current failing tests and pushing a fix for it. I'll mark the PR as ready to review as soon as all tests pass

[github-actions]

Semver Impact of This PR

🟡 Minor (new features)

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New Features ✨

• (baggage) Added double baggage prevention logic by harshit078 in #19597

• (remix) Server Timing Headers Trace Propagation by onurtemizkan in #18653

Bug Fixes 🐛

Deps

• Bump next to 15.5.13/16.1.7 to fix CVE-2026-1525, CVE-202-33036 and related by chargome in #19870
• Bump devalue 5.6.3 to 5.6.4 to fix CVE-2026-30226 by chargome in #19849
• Bump file-type to 21.3.2 and @nestjs/common to 11.1.17 by chargome in #19847
• Bump unhead 2.1.4 to 2.1.12 to fix CVE-2026-31860 and CVE-2026-31873 by chargome in #19848
• Bump flatted 3.3.1 to 3.4.2 to fix CVE-2026-32141 by chargome in #19842
• Bump tar 7.5.10 to 7.5.11 to fix CVE-2026-31802 by chargome in #19846
• Bump hono 4.12.5 to 4.12.7 in cloudflare-hono E2E test app by chargome in #19850
• Bump undici 6.23.0 to 6.24.1 to fix multiple CVEs by chargome in #19841

Other

• (cloudflare) Use correct env types for withSentry by JPeer264 in #19836
• (core) Align error span status message with core SpanStatusType for langchain/google-genai by nicohrubec in #19863
• (deno) Clear pre-existing OTel global before registering TracerProvider by sergical in #19723
• (node-core) Recycle propagationContext for each request by Lms24 in #19835

Internal Changes 🔧

• (deps) Bump next from 16.1.5 to 16.1.7 in /dev-packages/e2e-tests/test-applications/nextjs-16 by dependabot in #19851
• (nextjs) Skip broken ISR tests by chargome in #19871
• (react) Add gql tests for react router by chargome in #19844
• (release) Switch from action-prepare-release to Craft by BYK in #18763

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