[pnpm-sync-lib] Improve approach to console logging

[octogonz]

From https://github.com/microsoft/rushstack/pull/4530/files#r1504932679:

2. Also I would suggest to improve the formatting of the message:

   pnpm-sync: Copied 107 files in 95ms from C:\Git\rushstack\libraries\terminal
   

3. It seems pnpmSyncCopy() is printing this message directly to the console. We should improve the API to provide a messaging callback that allows the output to be redirected and (ideally) optionally reformatted. Something like this:

   pnpmSyncCopy({
     pnpmSyncJsonPath,
     messageCallback: ({ message, messageKind: 'error'|'warning'|'info'|'verbose'|'timing', messageId, details }) => {
       if (messageKind === 'verbose' && !debug) {
         return;
       }
       switch (messageId) {
         case 'sync-finished':
           // customized logging; the structure of details can depend on messageId
           terminal.writeLine(colors.green('pnpm-sync') 
             + ` copied ${details.fileCount} files in ${details.totalMs} ms from ${details.sourcePath}`);
           break;
         default:
           // simple preformatted logging
           if (messageKind === 'error' | messageKind === 'warning') {
             console.error(message);
           } else {
             console.log(message);
           }
           break;
       }
     }
   })

   This would ensure that Rush (and in the future PNPM) has full ownership of its CLI UX.

[octogonz]

This message can also be improved:

Generate pnpm-sync.json ...
The pnpm-lock.yaml file path => C:\Git\rushstack\common\temp\pnpm-lock.yaml
The .pnpm folder path => C:\Git\rushstack\common\temp\node_modules\.pnpm
pnpm-sync prepare: 51.144ms

Maybe something like this:

For a normal and --verbose build:

Regenerated pnpm-sync.json in 51ms.

For a --debug build:

pnpm-sync-prepare: Starting operation...
pnpm-sync-prepare: lockfile path is C:\Git\rushstack\common\temp\pnpm-lock.yaml
pnpm-sync-prepare: .pnpm path is C:\Git\rushstack\common\temp\node_modules\.pnpm
Regenerated pnpm-sync.json in 51ms.