Hiding and showing Play button depending on the current execution mode

[vitvakatu]

The Play button should be visible only in a mode with one or more execution contexts disabled. It means the button must be hidden in live, but visible in design. This behavior can be hard coded.

Also, a second state for the Play icon must be added – a rotating spinner. This spinner would be displayed when the execution is in progress after pressing the button. The spinner should be animated on GPU similar to our blinking cursor.

Only visual changes for the button are in the scope of this task. For testing, new temporary shortcuts can be added to show/hide the button on demand and to enable/disable the spinner.

Acceptance Criteria

GIVEN an opened IDE
WHEN the current execution mode is `live`
THEN The Play button is not visible on the execution mode dropdown

WHEN the current execution mode is `design`
THEN The Play button is visible and can be clicked.

WHEN I press the button
THEN A rotating spinner is displayed instead of Play icon.

[enso-bot]

Stijn Seghers reports a new STANDUP for today (2023-04-07):

Progress: Started defining a spinner icon and abstracting away the play button area of the execution environment selector. It should be finished by 2023-04-14.

[enso-bot]

Stijn Seghers reports a new STANDUP for today (2023-04-11):

Progress: After a day of distractions, managed to abstract away the play button area of the execution environment selector. Actually showing/hiding the button is the final step. It should be finished by 2023-04-14.

[enso-bot]

Stijn Seghers reports a new STANDUP for today (2023-04-12):

Progress: Clicking the play button now turns it into a spinner. It also hides the play button when the active execution environment doesn't have any context disabled. Created a PR. It should be finished by 2023-04-14.