Feature: Auto-submit predefined prompt in Sidebar

Please add support for predefined prompts that are sent immediately.

Desired behavior (either/both)

1. On Sidebar open:
   Automatically send a selected predefined prompt.
2. Dedicated shortcut:
   A shortcut that opens the Sidebar (if closed) and immediately sends a selected predefined prompt.

Example

Ctrl+Shift+S → opens Sidebar → sends “Summarize this webpage”.

Notes

• Prompt should be selectable in settings.
• If possible, allow multiple shortcut→prompt mappings.

UX benefit

This would be great for UX: it makes interaction with Page Assist and webpages much faster and easier, especially for frequent actions.