Provide ability to cancel a scan

[JustEmrick]

Description:

Currently, a scan occasionally encounters a stall or remains in a queued status during scans. To enhance user experience and control, we should consider implementing a feature that allows users to cancel scans that are stuck or queued, ensuring smoother scanning processes and efficient use of resources. Even for scans that are running but the user decides to terminate

Problem Statement:

Sometimes when I use this scanner, I experience occasional scans that become stuck at 50% progress or remain in a queued status indefinitely.

User Stories:

As a user, I want the ability to cancel a scan that is stalled or queued, so that I can free up system resources and initiate a fresh scan.

Acceptance Criteria:

• A "Cancel" button should be available for scans that are stalled or queued. Clicking this button should stop the scan process and provide a prompt for confirmation.

As a user, I want the ability to cancel a scan that is currently running, so that I can start over or initiate a fresh scan.

Acceptance Criteria:

• A "Cancel" button should be available for scans that are currently running. Clicking this button should stop the scan process and provide a prompt for confirmation.

As a user, I want to receive a notification when a scan is cancelled successfully, so that I am informed about the outcome of my action.

Acceptance Criteria:

• A new status should be displayed to the user when they successfully cancel a scan.

As a user, I don't want the option to cancel a scan that has already completed, so that I am not able to perform an action is not applicable.

Acceptance Criteria:

• There is no ability for a user to attempt to cancel a scan that has already completed

As a user, I want the ability to view cancelled scans from in my scans list, so that I maintain a record of all attempted scans on my assets

Acceptance Criteria:

• When a user views the scans tab, cancelled scans are still displayed and the user interface should reflect the cancelled status.

[zimventures]

Closed out via #176