release(runway): cherry-pick chore: reduce Sentry trace sampling cp-13.40.0

[runway-github]

• chore: reduce Sentry trace sampling cp-13.40.0 (chore: reduce Sentry trace sampling cp-13.40.0 #44451)

Description

Reduce Sentry trace sampling rate to reduce the changes we'll spend all
of our performance quota prematurely in the future. Lately we've
accidentally over-spent a few times, this would give us more of a
buffer.

Changelog

CHANGELOG entry: null

Related issues

N/A

Manual testing steps

N/A

Screenshots/Recordings

N/A

Pre-merge author checklist

• I've followed MetaMask Contributor
  Docs and MetaMask
  Extension Coding
  Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format
  if applicable
• I’ve applied the right labels on the PR (see labeling
  guidelines).
  Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the
  app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described
  in the ticket it closes and includes the necessary testing evidence such
  as recordings and or screenshots.

---

Note

Low Risk
Single numeric tuning for observability volume; no auth, data
handling, or functional behavior changes.

Overview
Lowers the default Sentry tracesSampleRate for production
extension builds from 0.75% to 0.5% in getTracesSampleRate
(setupSentry.js).

CI branch rates, METAMASK_DEBUG (1.0), fake DSN, and manifest
flags.sentry.tracesSampleRate overrides are unchanged—only the
fallback when none of those apply.

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Co-authored-by: Vaibhav Goyal 57912679+v-goyal@users.noreply.github.com 8b02f4a

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[gauthierpetetin]

No release label on PR. Adding release label release-13.40.0 on PR, as PR was cherry-picked in branch 13.40.0.