fix: disable Show Digital Twin button when counterPartyId unavailable

[jalvaro-lks]

WHAT

Disables the "Show Digital Twin" button in Passport Consumption when counterPartyId is unavailable. Updates button styling to reflect disabled state and adds informative snackbar notifications when clicked.

WHY

The button was remaining enabled despite counterPartyId not being available from the backend, allowing users to click it and view an empty modal panel. Disabling the button prevents confusing user experience and provides clear feedback that the feature is not yet available.

FURTHER NOTES

• Updated handleShowDigitalTwin() handler to validate both digitalTwinData and counterPartyId before opening modal
• Button styling now conditionally applies active gradient only when both conditions are met
• Added specific error messages in snackbar notifications to indicate which data is missing

Closes #559