fix: convert scanner.sh to LF line endings and enforce for all shell scripts

- Convert .github/scanner.sh from CRLF to LF line endings
- Add .gitattributes to enforce LF for *.sh files
- Update .editorconfig with explicit shell script settings
- Prevents line ending issues on Linux/WSL execution

.editorconfig

@@ -27,3 +27,8 @@ csharp_style_var_for_built_in_types = false:silent
 csharp_style_var_when_type_is_apparent = true:suggestion
 # Prefer explicit types in other cases to improve readability of math formulas
 csharp_style_var_elsewhere = false:silent
+# Shell scripts
+[*.sh]
+end_of_line = lf
+indent_style = space
+indent_size = 2

.gitattributes

@@ -0,0 +1,23 @@
+# Git Line Ending Configuration for QuanTAlib
+
+# Default behavior: let Git normalize line endings to LF on checkin
+* text=auto
+
+# Shell scripts must always use LF
+*.sh text eol=lf
+
+# Windows-specific files use CRLF
+*.bat text eol=crlf
+*.cmd text eol=crlf
+*.ps1 text eol=crlf
+
+# Binary files
+*.png binary
+*.jpg binary
+*.jpeg binary
+*.gif binary
+*.ico binary
+*.dll binary
+*.exe binary
+*.snupkg binary
+*.nupkg binary