fixes #20132; fixes the broken jsondoc comand [backport]

[ringabout]

fixes #20132

todo

• tests

[ringabout]

proc doSomething*(x, y: int): int =
  ## seed
  x + y

const
  a* = 1 ## echo 1234
  b* = "test"

type
  MyEnum* = enum
    foo, bar

outputs

{
  "orig": "C:\\Users\\blue\\Desktop\\Nim\\testexe.nim",
  "nimble": "compiler",
  "moduleDescription": "",
  "entries": [
    {
      "name": "doSomething",
      "type": "skProc",
      "line": 1,
      "col": 0,
      "code": "proc doSomething(x, y: int): int {.raises: [], tags: [], forbids: [].}",
      "signature": {
        "return": "int",
        "arguments": [
          {
            "name": "x",
            "type": "int"
          },
          {
            "name": "y",
            "type": "int"
          }
        ],
        "pragmas": [
          "raises: []",
          "tags: []",
          "forbids: []"
        ]
      },
      "description": "seed"
    },
    {
      "name": "a",
      "type": "skConst",
      "line": 6,
      "col": 2,
      "code": "a = 1",
      "description": "echo 1234"
    },
    {
      "name": "b",
      "type": "skConst",
      "line": 7,
      "col": 2,
      "code": "b = \"test\""
    },
    {
      "name": "MyEnum",
      "type": "skType",
      "line": 10,
      "col": 10,
      "code": "MyEnum = enum\n  foo, bar"
    }
  ]
}

[github-actions]

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