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## Summary - Replace all `ubuntu-latest-4-cores` (paid larger runners) with `ubuntu-latest` across CI workflows - The free `ubuntu-latest` runner for public repos already provides **4 vCPUs + 16 GB RAM** — identical specs to the paid 4-core larger runner - Affects 4 workflow files: `ci-server.yaml`, `ci-front.yaml`, `ci-sdk.yaml`, `ci-zapier.yaml` (8 job definitions total, including the 10-shard integration test matrix) - The `ubuntu-latest-8-cores` runners are intentionally **kept** for memory-heavy jobs (frontend build, storybook build, E2E tests) where the extra capacity (8 vCPUs, 32 GB RAM) is needed