Add Rename to the component right-click menu

Rename is offered from both the canvas and the navigation tree. Names are
checked against Sedona's Component.checkName rules (1-7 ASCII chars, a
letter first, then letters, digits or '_') and must be unique among
siblings. In file mode link paths through the old name are rewritten and
the rename is one undo step; in live mode it goes to the device via Sox
and warns if the device rejects it.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

undo.py

@@ -248,3 +248,25 @@ class DeleteComponentCommand:
                 links_parent.remove(link)
         if self.element in list(self.parent):
             self.parent.remove(self.element)
+
+
+class RenameComponentCommand:
+    """A rename, plus every link whose path ran through the component's old name."""
+
+    def __init__(self, element, old_name, new_name, link_changes, label="rename"):
+        # link_changes: list of (link_element, attr, old_value, new_value)
+        self.element = element
+        self.old_name = old_name
+        self.new_name = new_name
+        self.link_changes = link_changes
+        self.label = label
+
+    def undo(self):
+        self.element.set("name", self.old_name)
+        for link, attr, old_value, _ in self.link_changes:
+            link.set(attr, old_value)
+
+    def redo(self):
+        self.element.set("name", self.new_name)
+        for link, attr, _, new_value in self.link_changes:
+            link.set(attr, new_value)