refactor: inspect/debugging as useInspector

This PR rewrites the logic for establishing a connection with the debugging socket, and adds some enhancements along the way.  Part of solving #188. Some highlights -

- I've installed `"devtools-protocol`, a convenient package that has the static types for the devtools protocol (duh) autogenerated from chrome's devtools codebase.
- We now log messages and exceptions into the terminal directly, so you don't have to open devtools to see those messages.
- Messages are now buffered until a devtools instance connects, so you won't lose any messages while devtools isn't connected.
- We don't lose the connection on making changes to the worker, removing the need for the kludgy hack on the devtools side (where we refresh the whole page when there's a change)

Some things that I still have to do, and will do so in followup PRs -
- clear the console whenever we make a change to the worker
- stay connected when we shift between local/remote mode
- eventually, move to using the devtools hosted at cloudflareworkers.com.

Author: threepointone

package-lock.json

@@ -59,6 +59,7 @@
     "chokidar": "^3.5.2",
     "clipboardy": "^3.0.0",
     "command-exists": "^1.2.9",
+    "devtools-protocol": "^0.0.955664",
     "execa": "^6.0.0",
     "faye-websocket": "^0.11.4",
     "finalhandler": "^1.1.2",