refactor: replace inline note with callout component for consistency

- Use x-callout component in developer view for env var note
- Simplify label text from "Comment (Optional)" to "Comment"
- Minor code formatting improvements via Pint

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

bootstrap/helpers/shared.php

@@ -446,7 +446,7 @@ function parseEnvFormatToArray($env_file_contents)
             $remainder = '';
 
             // Check if value starts with quotes
-            $firstChar = isset($value_and_comment[0]) ? $value_and_comment[0] : '';
+            $firstChar = $value_and_comment[0] ?? '';
             $isDoubleQuoted = $firstChar === '"';
             $isSingleQuoted = $firstChar === "'";