feat(agent-core-v2): add the L3 unit layer and the Feature seam - #2678

Node.js 20 is deprecated. The following actions target Node.js 20 but are being forced to run on Node.js 24: actions/checkout@v4. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/

"path" also has a named export "basename"

"path" also has a named export "join"

"path" also has a named export "join"

"path" also has a named export "join"

"path" also has a named export "join"

Function declared in a loop contains unsafe references to variable(s)

Function declared in a loop contains unsafe references to variable(s)

The catch parameter "err" should be named "error"

The catch parameter "handlerErr" should be named "error"