refactor: Trim whitespace from end of each line in table output

Co-authored-by: aider (openai/andrew/openrouter/deepseek/deepseek-chat-v3.1) <aider@aider.chat>

src/modes/common.rs

@@ -140,6 +140,14 @@ pub fn settings_output_format(settings: &config::Settings) -> OutputFormat {
         .unwrap_or(OutputFormat::Table)
 }
 
+/// Trim whitespace from the end of each line in a string
+pub fn trim_lines_end(s: &str) -> String {
+    s.lines()
+        .map(|line| line.trim_end())
+        .collect::<Vec<&str>>()
+        .join("\n")
+}
+
 /// Create a table with consistent styling and terminal detection
 pub fn create_table(use_styling: bool) -> Table {
     let mut table = Table::new();