some fixes and improvements to build

- change .yarn/ gitignore to include subprojects
- add nodejs-rfb to build (and bump it)
- add clean script

Justfile

@@ -1,5 +1,6 @@
 all:
 	yarn workspace @cvmts/cvm-rs run build
+	yarn workspace @computernewb/nodejs-rfb run build
 	yarn workspace @cvmts/shared run build
 	yarn workspace @cvmts/qemu run build
 	yarn workspace @cvmts/cvmts run build