Fix Manage Kits for apps read from a device

The schema built from a Sox session spelled checksums as signed decimals,
so no kit matched a manifest: Installed showed raw checksums and Action
read "Keep at checksum ...". They are now 8 hex digits like a .sax file,
and checksums compare regardless of zero-padding.

A device session only loads folders as they are opened, so only sys
counted as used. Used kits now come from the whole component tree, read
one request at a time so a small controller is not flooded into dropping
the session.

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

sax_file.py

@@ -501,6 +501,18 @@ def used_kit_names():
     if app_state.xml_root_element is None:
         return names
 
+    # A device session's DOM only holds the folders opened so far.
+    session = app_state.device_session
+    if session is not None and session.is_connected:
+        try:
+            return session.used_kit_names()
+        except Exception as error:
+            messagebox.showwarning(
+                "Kits",
+                f"Could not read every component from the device:\n{error}\n\n"
+                "Kits shown as used come only from the folders opened so far.",
+            )
+
     for comp in app_state.xml_root_element.iter("comp"):
         type_str = comp.get("type") or ""
         if "::" in type_str: