Add data-urlencode option guidance

Changes in this MR

Updates the REST API style guide by adding a new section about using cURL's --data-urlencode option for sending data that contains special characters.

The addition explains when to use this option (for text with quotes, ampersands, regular expressions, or markdown content) and provides three practical examples:

• Posting data with special characters
• Deleting items using regex patterns
• Uploading file content

The change also includes a minor grammar fix, changing "will create" to "creates" in an existing sentence.

Review app

• Preview link: Post data using cURL’s --data-urlencode

Related issues

• Docs: Update API docs guidance on --data use (#582683 - closed)