do not change address bar content if no query was made in the Duck.ai Input Screen (#6306)

Task/Issue URL:
https://app.asana.com/1/137249556945/project/1208671518894266/task/1210657930367705?focus=true

### Description
Revert back to the original omnibar content if Duck.ai Input screen
query was not submitted.

### Steps to test this PR

- [ ] Go to any website
- [ ] Open input screen and change content
- [ ] Go back
- [ ] Verify the website URL is restored in the omnibar

Author: LukasPaczos

app/src/main/java/com/duckduckgo/app/browser/BrowserTabFragment.kt

@@ -873,7 +873,7 @@ class BrowserTabFragment :
             if (result.resultCode == RESULT_OK) {
                 submitQuery(query)
             } else {
-                omnibar.setText(query)
+                omnibar.setDraftTextIfNtp(query)
             }
         }
 

app/src/main/java/com/duckduckgo/app/browser/omnibar/Omnibar.kt

@@ -463,6 +463,10 @@ class Omnibar(
     ) {
         newOmnibar.decorate(Decoration.NewTabScrollingState(canScrollUp, canScrollDown, topOfPage))
     }
+
+    fun setDraftTextIfNtp(query: String) {
+        newOmnibar.setDraftTextIfNtp(query)
+    }
 }
 
 fun VisualDesignExperimentDataStore.getOmnibarType(): OmnibarType {

app/src/main/java/com/duckduckgo/app/browser/omnibar/OmnibarLayout.kt

@@ -1037,4 +1037,8 @@ open class OmnibarLayout @JvmOverloads constructor(
     override fun onAnimationFinished() {
         omnibarTextListener?.onTrackersCountFinished()
     }
+
+    fun setDraftTextIfNtp(query: String) {
+        viewModel.setDraftTextIfNtp(query)
+    }
 }

app/src/main/java/com/duckduckgo/app/browser/omnibar/OmnibarLayoutViewModel.kt

@@ -826,4 +826,15 @@ class OmnibarLayoutViewModel @Inject constructor(
         //     }
         // }
     }
+
+    fun setDraftTextIfNtp(query: String) {
+        if (_viewState.value.viewMode is NewTab) {
+            _viewState.update {
+                it.copy(
+                    omnibarText = query,
+                    updateOmnibarText = true,
+                )
+            }
+        }
+    }
 }