Lessc to provide preserve comments option

lessc should provide an option for comments to be preserved. Currently it preserves block comments and removes inline or // comments.

To reproduce:

// Main comment
/** comment with block **/
body {
  width: 100%; // inline comment
}

Current behavior:

/** comment with block **/
body {
  width: 100%;
}

Expected behavior:

/** Main comment **/
/** comment with block **/
body {
  width: 100%; /** inline comment **/
}

Environment information:

• less version: v4.2.0
• nodejs version: v18.18.0
• operating system: macos

Start at the lessc command-line entry point and trace how comments are currently handled for the reproduction shown in the issue. Add a preserve-comments option whose output retains the line and inline comments, then verify the expected CSS behavior against the supplied example.