frontend: turning on message logging in browser console for front-end-dev
frontend: adding module json files to front-end-dev
devtools: sending missing messages to fix add/remove breakpoint

- 'Runtime.executionContextCreated' invoked after we supply the resource tree
- 'Debugger.scriptParsed' invoked for every script for which we supply resource content
- these may move to different places in the future and be invoked at different stages, but for now this suffices to make the breakpoint API work
docs: debugging debugium