fix(shirelang): ensure null safety in ShireVcsSingleAction #78

Update the `ShireVcsSingleAction` to handle null cases properly. This prevents the action from crashing when no configurations are available. The changes include:
- Using `firstOrNull` to safely retrieve the first configuration.
- Adding a null check before accessing properties of `hobbitHole`.
- Returning early if `firstOrNull` returns null in the `actionPerformed` method.

shirelang/src/main/kotlin/com/phodal/shirelang/actions/vcs/ShireVcsSingleAction.kt

@@ -17,19 +17,20 @@ class ShireVcsSingleAction : DumbAwareAction() {
     override fun update(e: AnActionEvent) {
         val isOnlyOneConfig = shireActionConfigs().size == 1
 
-        val hobbitHole = shireActionConfigs().firstOrNull()?.hole ?: return
+        val hobbitHole = shireActionConfigs().firstOrNull()?.hole
         e.presentation.isVisible = isOnlyOneConfig
-        e.presentation.isEnabled = hobbitHole.enabled
-
-        e.presentation.text = hobbitHole.name ?: "<Placeholder>"
+        e.presentation.isEnabled = hobbitHole != null && hobbitHole.enabled
+        if (hobbitHole != null) {
+            e.presentation.text = hobbitHole.name ?: "<Placeholder>"
+        }
     }
 
     override fun actionPerformed(e: AnActionEvent) {
         val project = e.project ?: return
 
         VariableActionEventDataHolder.putData(VariableActionEventDataHolder(e.dataContext))
 
-        val config = shireActionConfigs().first()
+        val config = shireActionConfigs().firstOrNull() ?: return
         ShireRunFileAction.executeShireFile(project, config, null)
     }
 }