add ask mode (#58594)

Author: mpchenette

content/copilot/concepts/billing/copilot-requests.md

@@ -39,7 +39,7 @@ The following {% data variables.product.prodname_copilot_short %} features can u
 
 | Feature | Premium request consumption | SKU Attribution |
 | ------- | ----------- | ----------- |
-| [{% data variables.copilot.copilot_chat_short %}](/copilot/using-github-copilot/copilot-chat) | {% data variables.copilot.copilot_chat_short %} uses **one premium request** per user prompt, multiplied by the model's rate. This includes edit, agent, and plan modes in {% data variables.copilot.copilot_chat_short %} in an IDE. | {% data variables.product.prodname_copilot_short %} premium requests |
+| [{% data variables.copilot.copilot_chat_short %}](/copilot/using-github-copilot/copilot-chat) | {% data variables.copilot.copilot_chat_short %} uses **one premium request** per user prompt, multiplied by the model's rate. This includes ask, edit, agent, and plan modes in {% data variables.copilot.copilot_chat_short %} in an IDE. | {% data variables.product.prodname_copilot_short %} premium requests |
 | [{% data variables.copilot.copilot_cli_short %}](/copilot/concepts/agents/about-copilot-cli) | Each prompt to {% data variables.copilot.copilot_cli_short %} uses **one premium request** with the default model. For other models, this is multiplied by the model's rate. | {% data variables.product.prodname_copilot_short %} premium requests |
 | [{% data variables.product.prodname_copilot_short %} code review](/copilot/using-github-copilot/code-review/using-copilot-code-review) | When you assign {% data variables.product.prodname_copilot_short %} as a reviewer for a pull request, **one premium request** is used each time {% data variables.product.prodname_copilot_short %} posts comments to the pull request. | {% data variables.product.prodname_copilot_short %} premium requests |
 | [{% data variables.copilot.copilot_coding_agent %}](/copilot/concepts/about-copilot-coding-agent) | {% data variables.copilot.copilot_coding_agent %} uses **one premium request** per session, plus **one premium request** for each real-time steering comment made during an active session. A session begins when you ask {% data variables.product.prodname_copilot_short %} to create a pull request or make one or more changes to an existing pull request. | {% data variables.copilot.copilot_coding_agent %} premium requests |