Fix Git editor reword workflow and UI coverage

- show Git editor file paths instead of the submitted git command
- surface follow-up commit message editors during interactive rebase reword
- add rename-commit UI tests for editor and amend-message solution paths
- add broader embedded level solution scenarios for alternate Git workflows

app/src/main/java/solutions/tretter/githugandroid/levels/SquashLevel.kt

@@ -39,6 +39,12 @@ internal fun squashLevel(): Level = level(
             "git reset --soft HEAD~4",
             "git commit -m \"New commit message\"",
         ),
+        levelTestCase(
+            "mixed reset add and recommit",
+            "git reset HEAD~4",
+            "git add README",
+            "git commit -m \"New commit message\"",
+        ),
     ),
     negativeTestCases = listOf(
         levelTestCase("reset without replacement commit", "git reset --soft HEAD~4"),