chore(client): bump chart 1.3.1 -> 1.3.2 (hourly auto-upgrade)

[saadqbal]

Summary

• Bumps client/Chart.yaml version and appVersion from 1.3.1 → 1.3.2.
• Updates client/MIGRATION.md to reflect the new auto-upgrade cadence (hourly at :23 UTC) shipped in chore(auto-upgrade): run cronjob hourly at :23 (prod cherry-pick) #113.
• After merge, tagging v1.3.2 on the resulting main commit triggers release-helm-chart.yaml, which packages the chart and publishes to gh-pages so https://tracebloc.github.io/client serves 1.3.2.

This is the prod-side bump. A companion PR mirrors the same change onto develop so dev does not drift backwards relative to main.

Refs #111.

Test plan

• helm lint --strict ./client -f client/ci/eks-values.yaml clean
• helm unittest client/ — 116/116 pass at 1.3.2
• After merge, tag v1.3.2 and confirm release-helm-chart.yaml publishes the new .tgz to gh-pages
• After publish, observe a 1.3.1 client self-upgrade to 1.3.2 within an hour

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