fix: clarify conflict pane roles and status indicators

Use Resolution and Other version borders, omit branch/path metadata,
and show unsaved output state only on the writable pane. Track native
explorer conflict C from authoritative jj state across draft/check/error
transitions and clear it only after confirmed resolution.

Focused resolver and save tests pass; live terminal labels and explorer
verified without saving the mock conflicts. Full library run: 795 pass,
one unrelated async plugin fixture_barrier startup failure.

src/diff.rs

@@ -359,8 +359,8 @@ impl DiffState {
     }
     pub(crate) fn set_resolver_paths(&mut self, root: PathBuf, paths: Vec<PathBuf>, file: usize) {
         let comparison = self.comparison.get_or_insert_with(|| Comparison {
-            before: "Draft".into(),
-            after: "Alternative".into(),
+            before: "Resolution".into(),
+            after: "Other version".into(),
             files: Vec::new(),
             root: root.clone(),
             editable_paths: BTreeSet::new(),
@@ -432,7 +432,7 @@ impl DiffState {
         self.loading = false;
         self.pending = None;
         self.request_kind = None;
-        self.side_labels = ["Draft", "Alternative"];
+        self.side_labels = ["Resolution", "Other version"];
         self.comparison_id = Some(self.comparison_id.unwrap_or(0).wrapping_add(1));
         self.live_files.clear();
         let file = &mut self.comparison.as_mut().unwrap().files[self.file];
@@ -2465,6 +2465,12 @@ mod tests {
             files.entries().nth(files.selected).unwrap().path,
             Path::new("first.txt")
         );
+        assert!(!files.is_conflicted(Path::new("first.txt")));
+        state
+            .files
+            .as_mut()
+            .unwrap()
+            .set_conflicted(Path::new("first.txt"), true);
         state.set_resolver_paths(
             PathBuf::new(),
             vec!["binary.bin".into(), "first.txt".into(), "second.txt".into()],
@@ -2475,6 +2481,8 @@ mod tests {
             files.entries().nth(files.selected).unwrap().path,
             Path::new("second.txt")
         );
+        assert!(files.is_conflicted(Path::new("first.txt")));
+        assert!(!files.is_conflicted(Path::new("second.txt")));
     }
 
     fn excerpt_state(len: usize, changed: &[usize]) -> DiffState {