Add build configuration

[saulecabrera]

Right now the language server assumes that all projects are built through npm run asbuild, the build command should be configurable:

• npm run asbuild command might not be the default for all projects
• The default npm run asbuild builds the optimized and unoptmized wasm for the source files, which can result in delays for diagnostic reporting, minimizing the build command to a single command will reduce latency between diagnostic reports.

[saulecabrera]

With progressive compilation this is no longer required