Make NTP clock synchronization configurable and default to China-reachable servers - #25

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683, actions/setup-java@7a6d8a8234af8eb26422e24e3006232cccaa061b, github/codeql-action/analyze@f47c8e6a9bd05ef3ee422fc8d8663be7fe4bdc61, github/codeql-action/init@f47c8e6a9bd05ef3ee422fc8d8663be7fe4bdc61, gradle/actions/setup-gradle@d9c87d481d55275bb5441eef3fe0e46805f9ef70. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

Restore Gradle distribution 8.14.3 failed: Error: Cache service responded with 400

Failed to restore gradle-home-v1|Linux|analyze[cb94baee05a8998d3c82980ef86be61e]-ed20eeaf0320a0fb238c5c1b5fe39d351c21cb31: Error: Cache service responded with 400

Cannot build an overlay database because build-mode is set to "undefined" instead of "none". Falling back to creating a normal full database instead.