1156ba43bf
Two follow-ups from live Windows sessions: 1. agent/prompt_builder.py: extend the Windows shell hint with the native-binary path rule. Hermes disables MSYS path conversion for its bash, so agents passing /c/Users/... or /tmp/... to NATIVE programs (git -C, node, python, rg) hit 'cannot change to' / 'not found' while the same path works in bash builtins — observed repeatedly in a live session (git -C failures, git apply /tmp/x.patch failures). The hint now says: forward-slash native form (C:/Users/x) for native tools, $LOCALAPPDATA/Temp over /tmp for scratch files native tools read. (/tmp is pure model habit from Linux training data — nothing instructs it — so the hint is the right layer.) 2. tests: pin LF/CRLF preservation through write_file and patch_replace. A live session saw a repo-LF file come back full-CRLF after an edit (4699-line diff churn); not reproducible through current tool APIs, so pin the correct behavior — LF files stay LF, CRLF files stay CRLF, no mixed endings — to catch any regression on the Windows write path.