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/GitHugApp.kt

@@ -513,14 +513,20 @@ fun GitHugApp() {
 
         fun saveGitMessageEditor() {
             val state = gitMessageEditorState ?: return
-            val (newRepo, lines) = runtime.executeGitEditorCommand(
+            val result = runtime.executeGitEditorCommandWithResult(
                 level = currentLevel,
                 currentRepo = repo,
                 invocation = state.invocation,
                 message = state.content,
             )
             gitMessageEditorState = null
-            applyCommandResult(state.invocation.command, newRepo, lines, echoCommand = false)
+            applyCommandResult(state.invocation.command, result.repo, result.outputLines, echoCommand = false)
+            result.nextEditor?.let { nextEditor ->
+                gitMessageEditorState = GitMessageEditorState(
+                    invocation = nextEditor.invocation,
+                    content = nextEditor.content,
+                )
+            }
         }
 
         fun runCommand() {