When partial JSON tool call patterns appear in LLM output (e.g., from
quoting file content), the parser would incorrectly report them as
"incomplete tool calls", triggering auto-continue loops.
Fix: Added is_json_invalidated() to detect when partial JSON has been
invalidated by subsequent content that cannot be valid JSON:
- Unescaped newline inside a string (invalid JSON)
- Newline followed by prose text outside a string
The check is only applied to incomplete JSON - complete tool calls
with trailing text are still correctly detected.
Added 6 new tests covering:
- Tool results with partial JSON patterns
- LLM quoting file content inline vs on own line
- Comment prefixes (// # -- etc) with partial patterns
- Real incomplete tool calls (should still be detected)
d68f059acf