ui: preserve modern ISO state after template selection

Align the modern selector prop with DeployVM's existing isoHypervisor binding so the displayed ISO selection follows the parent fallback after template hypervisor changes. Restore focused watcher coverage for that state transition.

Author: Dogface2k

ui/src/views/compute/wizard/OsBasedImageSelection.vue

@@ -203,7 +203,7 @@ export default {
       type: Array,
       default: () => []
     },
-    selectedIsoHypervisor: {
+    isoHypervisor: {
       type: String,
       default: undefined
     },
@@ -226,7 +226,7 @@ export default {
       localSelectedImageType: this.selectedImageType,
       localSelectedGuestOsCategoryId: this.selectedGuestOsCategoryId,
       localRootDiskOverrideChecked: this.rootDiskOverrideChecked,
-      localSelectedIsoHypervisor: this.selectedIsoHypervisor
+      localSelectedIsoHypervisor: this.isoHypervisor
     }
   },
   mounted () {
@@ -260,7 +260,7 @@ export default {
     rootDiskOverrideChecked (newValue) {
       this.localRootDiskOverrideChecked = newValue
     },
-    selectedIsoHypervisor (newValue) {
+    isoHypervisor (newValue) {
       this.localSelectedIsoHypervisor = newValue
     }
   },

ui/tests/unit/views/compute/ImageSelectionHypervisor.spec.js

@@ -218,6 +218,17 @@ describe('compute image selection hypervisor state', () => {
     )
   })
 
+  it('synchronizes the modern ISO selector when the parent hypervisor changes', () => {
+    const context = { localSelectedIsoHypervisor: 'VMware' }
+
+    OsBasedImageSelection.watch.isoHypervisor.call(
+      context,
+      fallbackHypervisor
+    )
+
+    expect(context.localSelectedIsoHypervisor).toBe(fallbackHypervisor)
+  })
+
   it('preserves a modern explicit ISO hypervisor after selecting another ISO', () => {
     const selector = selectors[0]
     const { context, emit } = createContext(selector)