🐛 fix: make badge update script cross-platform compatible

- Detect macOS vs Linux sed syntax automatically
- Use appropriate sed command for each platform
- Fixes workflow failure in Docker container

macOS: sed -i '' (BSD sed)
Linux: sed -i (GNU sed)

scripts/update-all-badges.sh

@@ -25,21 +25,32 @@ if [ -n "$UNIT_COVERAGE" ]; then
     echo "  Unit: ${UNIT_COVERAGE}%"
 fi
 
+# Cross-platform sed command
+# Detect if we're on macOS (BSD sed) or Linux (GNU sed)
+SED_CMD=""
+if [[ "$(uname)" == "Darwin" ]]; then
+    # macOS - requires empty string after -i
+    SED_CMD="sed -i ''"
+else
+    # Linux - standard GNU sed
+    SED_CMD="sed -i"
+fi
+
 # Update BDD coverage badge if provided
 if [ -n "$BDD_COVERAGE" ] && grep -q "BDD_Coverage" README.md; then
-    sed -i '' "s/BDD_Coverage-[0-9.]\+-%/BDD_Coverage-${BDD_COVERAGE}-%/g" README.md
+    $SED_CMD "s/BDD_Coverage-[0-9.]\+-%/BDD_Coverage-${BDD_COVERAGE}-%/g" README.md
     echo "✅ BDD coverage badge updated to ${BDD_COVERAGE}%"
 fi
 
 # Update Unit coverage badge if provided
 if [ -n "$UNIT_COVERAGE" ] && grep -q "Unit_Coverage" README.md; then
-    sed -i '' "s/Unit_Coverage-[0-9.]\+-%/Unit_Coverage-${UNIT_COVERAGE}-%/g" README.md
+    $SED_CMD "s/Unit_Coverage-[0-9.]\+-%/Unit_Coverage-${UNIT_COVERAGE}-%/g" README.md
     echo "✅ Unit coverage badge updated to ${UNIT_COVERAGE}%"
 fi
 
 # Update main coverage badge if BDD coverage provided
 if [ -n "$BDD_COVERAGE" ] && grep -q "coverage-[0-9.]\+-%" README.md; then
-    sed -i '' "s/coverage-[0-9.]\+-%/coverage-${BDD_COVERAGE}-%/g" README.md
+    $SED_CMD "s/coverage-[0-9.]\+-%/coverage-${BDD_COVERAGE}-%/g" README.md
     echo "✅ Main coverage badge updated to ${BDD_COVERAGE}%"
 fi