Issue 23: Added progress indicators and cancellation (#34)

- Wrapped all table operations in a new foreground job context, which mediates foreground tasks.
- Added cancellation support and partial results for table read operations.
- Added the "mark" command, which can mark, unmark & toggle marked items
- Added support for alias arguments.
- Removed the "unmark" command, and replaced it as an alias to the "marked" command
- Fixed seg faults raised when there is no table shown in the result set.

internal/ssm-browse/controllers/ssmcontroller.go

@@ -77,7 +77,7 @@ func (c *SSMController) Clone(param models.SSMParameter) tea.Msg {
 }
 
 func (c *SSMController) DeleteParameter(param models.SSMParameter) tea.Msg {
-	return events.Confirm("delete parameter? ", func() tea.Msg {
+	return events.ConfirmYes("delete parameter? ", func() tea.Msg {
 		ctx := context.Background()
 		if err := c.service.Delete(ctx, param); err != nil {
 			return events.Error(err)