[Sealights][SLDEV-22556] - support instrumentation of defined npm script

[CubikNeRubik]

• A short explanation of the proposed change:

Extend the Sealights integration to support injection into any npm script command, not just npm start. This will enable support for commands like npm run start-dev, npm run dev, npm run server, etc.

• An explanation of the use cases your change solves

It will be possible to define run command for injection as npmRunScript parameter

VCAP_SERVICES

{
  "user-provided": [{
    "name": "sealights-service",
    "credentials": {
      "token": "xxx",
      "buildSessionId": "xxx",
      "npmRunScript": "start-dev"
    }
  }]
}

If it is not provided Sealight will be injected into start command for backward compatibility.

• I have viewed signed and have submitted the Contributor License Agreement

• I have made this pull request to the master branch

• I have added an integration test

[marcam-sl]

Hi @arjun024 and @robdimsdale, just checking in on our pending PR. Could you (or someone from your team) share the expected review timeline? Please let us know if any changes are needed — we’re aiming for this enhancement to be part of the next nodejs-buildpack release (post v1.8.39). Thanks!