dump nimbleDir

[fryorcraken]

The nimbleDir is a key configuration of nimble, and can be set via various means.

I suggest to add it to the nimble dump output.
Currently, it is not:

 nimble dump --json
{
  "name": "waku",
  "version": "0.36.0",
  "nimblePath": "/home/fryorcraken/src/waku-org/nwaku/waku.nimble",
  "author": "Status Research & Development GmbH",
  "desc": "Waku, Private P2P Messaging for Resource-Restricted Devices",
  "license": "MIT or Apache License 2.0",
  "skipDirs": [],
  "skipFiles": [],
  "skipExt": [],
  "installDirs": [
    "waku"
  ],
  "installFiles": [
    "waku.nim"
  ],
  "installExt": [],
  "requires": [
  ...
  ],
  "bin": [],
  "binDir": "",
  "srcDir": "",
  "backend": "c",
  "paths": [],
  "nimDir": "/home/fryorcraken/.nimble/bin",
  "entryPoints": [
    "waku.nim"
  ],
  "testEntryPoint": ""
}

▶ nimble --version
nimble v0.20.1 compiled at 2025-07-17 10:00:06
git hash: 9207e8b2bbdf66b5a4d1020214cff44d2d30df92