Provide a single "Copy full error message" button

Currently, when an error occurs, the full error details are split across multiple independent UI blocks. To copy the entire error information, I have to either:

- Switch back to the editor 2–3 times to gather the pieces, or
- Manually select all the text with the mouse.

Both approaches are extremely inconvenient, especially when I need the full context to investigate or report issues.

Proposed solution:

1. Add a single "Copy Full Error Message" button that copies all error details (including stack trace, line numbers, and any additional context) in one action.
2. Expose a command (e.g., editor.action.copyFullError) that can be assigned to a custom keyboard shortcut via the keybindings settings.