Docs: Difficulty configuring with GOOGLE_APPLICATION_CREDENTIALS

Users report confusion on usage of `GOOGLE_APPLICATION_CREDENTIALS.` The fix is to supply the absolute path to the SA JSON file in the env key of the config. For example:
```
"env": {
"CHRONICLE_PROJECT_ID": "1234...4321",
"CHRONICLE_CUSTOMER_ID": "...",
"CHRONICLE_REGION": "us",
"GOOGLE_APPLICATION_CREDENTIALS": "/Users/someusername/Projects/mcp-security/mysacreds.json"
},
```

We should update the ReadMe and the static-site docs to make this more clear.

**NOTE**: I thought we'd removed env from `cline_mcp_settings.json.example` and from docs because it was being conflated with `"--env-file"` in the `args` list but I now see that gti is using it for `VT_APIKEY`, so maybe it was only `--env-file` that we removed.

Maybe we need a little wizard to gather info and create the settings.json? I've seen many users stumble on path to the server dir, fail to prepend https, and other problems that we could catch when collecting the info.