fix(swc): support silent mode for running log

[vinubabu323]

Add a --silent option to build/start commands and pass it to the SWC compiler extras.

Suppress the SWC 'Running...' status line when silent mode is enabled or npm_config_loglevel is set to silent.

Also adds unit tests for the new SWC logging gate behavior.

Refs #3164

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior?

When SWC is used, the CLI always prints > SWC Running..., which makes stdout noisy and can break piping workflows expecting clean output.

Issue Number: #3164

What is the new behavior?

• Added --silent option to nest build and nest start

• Passed silent into SWC compiler extras

• Suppressed SWC Running... status log when:

  • --silent is passed
  • npm_config_loglevel=silent is set (e.g. npm run ... --silent)

• Default behavior remains unchanged when silent mode is not enabled

  Does this PR introduce a breaking change?

  [ ] Yes
  [x] No
  

  Other information

  Other information

• Validation:

  • npm run build
  • npx jest --runInBand --config test/jest-config.json

• Added unit tests in:

  • test/lib/compiler/swc/swc-compiler.spec.ts
  • Files changed:
    • commands/build.command.ts
    • commands/start.command.ts
    • actions/build.action.ts
    • lib/compiler/swc/swc-compiler.ts
    • test/lib/compiler/swc/swc-compiler.spec.ts

[vinubabu323]

Thanks for the approval. Since this still needs merge access, could @kamilmysliwiec please take a look when possible?

[kamilmysliwiec]

Could you rebase it to v12.0.0 branch?

[vinubabu323]

Rebased to v12.0.0. @kamilmysliwiec could you please review? Happy to make any further changes.

[kamilmysliwiec]

lgtm