SYN-6889: add missing ut and integration tests, report coverage and test results in CI, add README badges - #53

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@b4ffde65f46336ab88eb53be808477a3936bae11, actions/setup-go@93397bea11091df50f3d7e59dc26a7711a8bcfbe, golangci/golangci-lint-action@3a919529898de77ec3da873e3063ca4b10e7f5cc. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

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