v1.8.0: file manager improvements

- SFTP cleanup on app close and language switch
- Windows drive selector in local panel
- Browse and Refresh buttons for local panel
- Recursive upload/download/delete of folders
- Drag-and-drop between local and remote panels
- Sudo mode toggle for privileged file operations
- New i18n keys for EN/RU/ZH

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

gui/widgets/file_list.py

@@ -49,17 +49,23 @@ def _apply_dark_theme():
 
 
 class FileListWidget(ctk.CTkFrame):
-    """File list with columns, sorting, multi-selection."""
+    """File list with columns, sorting, multi-selection, drag-and-drop."""
 
     def __init__(self, master, columns: list[tuple[str, int]],
-                 on_navigate=None, on_select=None):
+                 on_navigate=None, on_select=None, on_drop=None):
         super().__init__(master, fg_color="#1e1e1e", corner_radius=6)
 
         self._on_navigate = on_navigate
         self._on_select = on_select
+        self._on_drop = on_drop
         self._items: list[dict] = []
         self._sort_col = None
         self._sort_reverse = False
+        self._drag_partner: "FileListWidget | None" = None
+        self._drag_start_x = 0
+        self._drag_start_y = 0
+        self._dragging = False
+        self._orig_fg_color = "#1e1e1e"
 
         _apply_dark_theme()
 
@@ -91,6 +97,11 @@ class FileListWidget(ctk.CTkFrame):
         self._tree.bind("<<TreeviewSelect>>", self._on_tree_select)
         self._tree.bind("<Return>", self._on_enter)
 
+        # Drag-and-drop bindings
+        self._tree.bind("<ButtonPress-1>", self._on_drag_start, add="+")
+        self._tree.bind("<B1-Motion>", self._on_drag_motion)
+        self._tree.bind("<ButtonRelease-1>", self._on_drag_release, add="+")
+
     def populate(self, items: list[dict]):
         """Fill list with items. Each item: {name, size, date, perm, is_dir}."""
         self._items = items
@@ -168,3 +179,46 @@ class FileListWidget(ctk.CTkFrame):
 
         self._items = dirs + files
         self.populate(self._items)
+
+    # ── Drag-and-drop ──
+
+    def set_drag_partner(self, partner: "FileListWidget"):
+        """Link two panels for drag-and-drop."""
+        self._drag_partner = partner
+
+    def _on_drag_start(self, event):
+        self._drag_start_x = event.x_root
+        self._drag_start_y = event.y_root
+        self._dragging = False
+
+    def _on_drag_motion(self, event):
+        if not self._drag_partner:
+            return
+        dx = abs(event.x_root - self._drag_start_x)
+        dy = abs(event.y_root - self._drag_start_y)
+        if not self._dragging and (dx > 10 or dy > 10):
+            sel = self.get_selected()
+            if sel and any(s["name"] != ".." for s in sel):
+                self._dragging = True
+                self._tree.configure(cursor="hand2")
+                self._drag_partner.configure(fg_color="#1e3a5f")
+
+    def _on_drag_release(self, event):
+        if not self._dragging or not self._drag_partner:
+            self._dragging = False
+            return
+        self._dragging = False
+        self._tree.configure(cursor="")
+        self._drag_partner.configure(fg_color=self._orig_fg_color)
+
+        # Check if mouse is over partner widget
+        px = self._drag_partner.winfo_rootx()
+        py = self._drag_partner.winfo_rooty()
+        pw = self._drag_partner.winfo_width()
+        ph = self._drag_partner.winfo_height()
+        mx, my = event.x_root, event.y_root
+
+        if px <= mx <= px + pw and py <= my <= py + ph:
+            items = [s for s in self.get_selected() if s["name"] != ".."]
+            if items and self._drag_partner._on_drop:
+                self._drag_partner._on_drop(items, self)