[Bug]: JSONLinesFileReader drops rows containing U+2028, U+2029 or U+0085 (uses str.splitlines) #2594

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• I have searched the existing issues and this bug is not already filed.
• My model is hosted on OpenAI or Azure. If not, please look at the "model providers" issue and don't file a new one here. (Not applicable: the bug is in the input reader, before any model call.)
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Describe the bug

JSONLinesFileReader.read_file splits the file with text.splitlines() (jsonl.py#L38). Python's str.splitlines() also breaks on U+2028 (LINE SEPARATOR), U+2029 (PARAGRAPH SEPARATOR) and U+0085 (NEXT LINE). JSON Lines uses only \n as the record separator, and those three characters are valid unescaped inside JSON strings. A valid row containing one of them is therefore cut into two fragments, neither of which parses. Each fragment is logged as Skipping malformed JSONL row in <path> at line N, so that row is dropped from the input (the rest of the file is still read), and the only trace is a warning.

(Side note: splitlines() also splits on \x0b, \x0c, \x1c, \x1d and \x1e. Those are control characters that must be escaped in JSON, so they cannot occur unescaped in a valid row and are not part of this bug.)

Steps to reproduce

File x.jsonl, where the first row contains a raw U+2028 between a and b (shown here as <LS>):

{"text":"a<LS>b"}
{"text":"c"}

docs = await JSONLinesFileReader(storage=storage).read_files()
print([d.text for d in docs])   # ['c']   (expected ['a
b', 'c'])
# log: Skipping malformed JSONL row in x.jsonl at line 1
#      Skipping malformed JSONL row in x.jsonl at line 2

json.loads('{"text":"a
b"}') parses fine on its own. The same happens with U+2029 and U+0085.

Expected Behavior

Both rows are read. Split on "\n" only and strip a trailing "\r" for CRLF files.

GraphRAG Config Used

input:
  type: jsonl

Logs and screenshots

Skipping malformed JSONL row in x.jsonl at line 1
Skipping malformed JSONL row in x.jsonl at line 2

Additional Information

• GraphRAG Version: 3.3.0 (graphrag-input at 5faaaf4)
• Operating System: macOS
• Python Version: 3.11
• Related Issues: JSONL reader skips entire file when input contains blank lines #2424 / PR Fix JSONL loader handling of blank/invalid lines #2434 (JSONL reader skipped the whole file on blank lines). That is a different bug in the same function; the splitlines() loop appears to have come in with that fix.

Suggested fix: for line_number, line in enumerate(text.split("\n"), start=1): line = line.rstrip("\r"), plus a test with U+2028 and U+0085 inside a string value.