Fix perspective-workspace and add monaco-editor-webpack-plugin compatibility to perspective-webpack-plugin

[texodus]

• Add support for multiplexing @finos/perspective and @finos/perspective-viewer modules to their ESM or UMD builds from the new esbuild script, which allows perspective-workspace to be subsequently used as a dependency without forcing a build type.

• Fix perspective-workspace package metadata to export the internal lumino components for integration into Lumino apps.

• Updates to the perspective-workspace theme:

  • Left-justified panel headers.
  • Add color level and border between <perspective-viewer> background and spacers.
  • Expand Global Filter resize bar to 8px, overlap layout left padding.
  • Remove Global Filter margins entirely.

• Add monaco option to @finos/perspective-webpack-plugin which allows disabling Monaco compilation, which makes it easier to embed Perspective in an application which uses its own monaco-editor and monaco-editor-webpack-plugin.

• Adds an example of Perspective + React + Monaco Editor in a single app, which uses Monaco's JSON support to show a live view of a <perspective-viewer> config.

  

[timkpaine]

this should take care of #1648? breaking change but will export the themes in src?

[texodus]

@timkpaine I hadn't planned on it but fair enough, I said I would. As mentioned, this is going to get deprecated fully soon anyway, as we extend perspective's theme support to allow UI driven theming, light/dark from user preferences, etc. I'm also going to remove the /themes/ references from /examples/, so these remappings will only be for integration.

As maybe I failed to mention, this backport will only work from webpack - CDN paths will need to be updated.