Parse GLM-4-0414 markerless tool calls (#491)

[aleroot]

Proposed changes

Fixes #491. Refs #481.

GLM-4-9B-0414 emits a tool call as the function name on its own line followed by the JSON arguments object, with no delimiters:

get_weather
{"location": "Paris", "unit": "celsius"}

Design

GLM-4-0414 is handled as a second dialect of the existing .glm4 format, opted in through a parser capability flag (supportsMarkerlessNamedJSON), the same pattern supportsBareJSON uses today. No new ToolCallFormat; existing formats are untouched.

Detection is schema-anchored: NamedJSONCallScanner matches a declared tool name at the start of a line, followed by a single newline and a balanced JSON object. Without declared tools the scanner does not exist, so ordinary word\n{...} prose can never be misread as a call.

Checklist

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• I have added tests that prove my fix is effective or that my feature works
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[CharlieTLe]

Some minor nits, but how should the following be supported:

write_file\n{"contents": "<tool_call>hello</tool_call> world"}

The current implementation would do:

write_file(contents: "hello world")

But is this the expected behavior?

[aleroot]

Some minor nits, but how should the following be supported:

write_file\n{"contents": "<tool_call>hello</tool_call> world"}

The current implementation would do:

write_file(contents: "hello world")

But is this the expected behavior?

@CharlieTLe thanks. this makes sense. GLM4 wrapper tags are now stripped only at payload boundaries, so literal tags inside JSON arguments are preserved. Added regression coverage as well.