fix: escape newlines in CopyButton JS string

Valid finding from PR review: copy button's JS string could break
on values with newlines. Added \n and \r escaping.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

compliance-dashboard/src/components/copy_button.rs

@@ -22,8 +22,12 @@ pub fn CopyButton(value: String, #[props(default = false)] small: bool) -> Eleme
             title: if copied() { "Copied!" } else { "Copy to clipboard" },
             onclick: move |_| {
                 let val = value.clone();
-                // Escape single quotes for JS
-                let escaped = val.replace('\\', "\\\\").replace('\'', "\\'");
+                // Escape for JS single-quoted string
+                let escaped = val
+                    .replace('\\', "\\\\")
+                    .replace('\'', "\\'")
+                    .replace('\n', "\\n")
+                    .replace('\r', "\\r");
                 let js = format!("navigator.clipboard.writeText('{escaped}')");
                 document::eval(&js);
                 copied.set(true);