New plugin API, viewer-charts features, replace @perspective-dev/viewer-openlayers

[texodus]

This PR introduces a new Plugin API which allows plugins to describe their configuration programmatically to the viewer the live in, allowing detailed plugin configuration without uilding custom configuration panels for each feature. In addition, this new core feature has been used as a basis to implement various side-quest updates to the new viewer-charts package.

This PR will break any custom plugin implementation.

viewer

• New condensed plugin API:
  • Consolidates small methods into one (single call) plugin_static_config
  • Adds plugin_config_schema and column_config_schema to controls column config options from JS.
  • Removes save (state is managed viewer side now).
• New tab bar for plugin_config menu and existing debug menu.
• Port to lightningCSS (internal).

viewer-charts

• Density and Maps chart packages (deprecates @perspective-dev/viewer-openlayers).
• Ported engine to run (optionally) in a web worker, with its own Client instance for direct Arrow slices from the engine without impacting the main thread.
• Implemented optional blit mode which copies frames to 2D Canvas instances to avoid the browser's GL context limit.
• Framerate benchmark suite which measures rendering (not calculation).
• Events (from d3fc).
• Export (from d3fc).