JSON parse errors should report the offending text

[starpit]

Describe the bug

pdl /tmp/foo.pdl

user: 3Attempted to parse ill-formed JSON: TypeError('the JSON object must be str, bytes or bytearray, not int')

To Reproduce

code: |
  result = 3
parser: json
lang: python

Expected behavior
Obviously in this simple example, the error message might be fine. Though it is strange to report JSON parse errors in terms of Python data types?

In a complex program with dynamic data, I think it becomes important to report the offending text that could not be parsed as JSON.

Screenshots
n/a

Desktop (please complete the following information):

• OS: macOS
• Browser n/a
• Version PDL 0.2.1.dev88+g334a253.d20250131

Additional context
n/a