fix(streaming): add helpful error message for malformed tool JSON in non-beta path

[tao-to-python]

Description

Fixes unhelpful raw parser error when model emits malformed JSON during streaming tool use, as reported in #1265.

Problem

The beta path (_beta_messages.py) already wraps from_json() with a helpful try-except:

try:
    content.input = from_json(json_buf, partial_mode=...)
except ValueError as e:
    raise ValueError(
        f"Unable to parse tool parameter JSON from model. "
        f"Please retry your request or adjust your prompt. "
        f"Error: {e}. JSON: {json_buf.decode('utf-8')}"
    ) from e

The non-beta path (_messages.py) was missing this wrapper, causing raw errors like:

ValueError: expected ident at line 1 column 11

No context about what JSON was received or what to do.

Solution

Add the same try-except wrapper to the non-beta accumulate_event() in _messages.py.

Changes

File	Change
src/anthropic/lib/streaming/_messages.py	Wrap from_json() with helpful ValueError

Fixes #1265

[AbdoKnbGit]

already fix that #1266