Refactor file handling and improve shell script robustness

- Replace `sed` with bash parameter expansion for file parsing
- Simplify conditionals and diff checks
- Use more robust shell practices
- Add explicit quoting and numeric comparisons

Author: vgrichina

apply-md

@@ -39,6 +39,8 @@ FILES_FILE="$TEMP_DIR/files.txt"
 cleanup() {
     rm -rf "$TEMP_DIR"
 }
+
+# Register cleanup on exit
 trap cleanup EXIT
 
 # Extract code blocks and their file names
@@ -110,8 +112,7 @@ apply_block() {
     fi
 
     # Check for changes
-    diff -q "$file" "$content_file" > /dev/null
-    if [ $? -eq 0 ]; then
+    if diff -q "$file" "$content_file" > /dev/null; then
         if [ "$VERBOSE" = true ]; then
             echo "No changes needed for: $file"
         fi

git-context

@@ -69,7 +69,8 @@ if [ -n "$status_output" ]; then
         # Extract the status code (first two characters)
         status_code="${line:0:2}"
         # Extract the filename (everything after the status code and whitespace)
-        file=$(echo "$line" | sed 's/^.. *//')
+        file=${line#??}
+        file=${file#"${file%%[! ]*}"} # Remove leading whitespace
         status_desc=""
 
         # Determine the status description
@@ -89,10 +90,10 @@ if [ -n "$status_output" ]; then
 fi
 
 # Show recent commits
-if [ $RECENT_COMMITS -gt 0 ]; then
+if [ "$RECENT_COMMITS" -gt 0 ]; then
     echo "## Recent Commits (for reference)"
     echo ""
-    git log -n $RECENT_COMMITS --pretty=format:"- %h: %s (%an, %ar)" | while read -r line; do
+    git log -n "$RECENT_COMMITS" --pretty=format:"- %h: %s (%an, %ar)" | while read -r line; do
         echo "$line"
     done
     echo ""