Manage Kits as embedded panel, fix checksum zero-padding mismatch

Manage Kits now opens inside the editor pane (like Properties and Link
View) instead of a separate Toplevel window. Also normalize hex
checksums by stripping leading zeros so .kit and manifest filenames
that disagree on padding (e.g. 462d43e vs 0462d43e) still resolve to
a version.

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

main.py

@@ -111,11 +111,12 @@ zoom_label = None
 menu_view = None
 show_left_column_var = None
 
-# The Properties and Link views each take the editor pane over from the canvas rather
-# than floating above it, so at most one of the three is on screen and these two say
-# which. Both None means the sheet is showing.
+# The Properties, Link and Kits views each take the editor pane over from the canvas
+# rather than floating above it, so at most one of the four is on screen and these three
+# say which. All None means the sheet is showing.
 properties_panel = None
 link_panel = None
+kits_panel = None
 
 # The sheet to put the tree back on when a sheet change is refused because of unsaved
 # edits, and the flag that stops the restoring selection from being read as a fresh
@@ -204,7 +205,7 @@ def delete_component(comp):
 
 def editor_panel_showing():
     """Whether something other than the wiresheet has the editor pane."""
-    return properties_panel is not None or link_panel is not None
+    return properties_panel is not None or link_panel is not None or kits_panel is not None
 
 
 def _take_editor_pane():
@@ -316,17 +317,54 @@ def dismiss_link_view(restore_canvas=True):
         _give_editor_pane_back()
 
 
+def show_kits():
+    """Puts the kit table in the editor pane, in place of the wiresheet."""
+    global kits_panel
+    if app_state.xml_root_element is None:
+        messagebox.showinfo("Manage Kits", "Open a SAX file first.")
+        return
+    if app_state.xml_root_element.find("schema") is None:
+        messagebox.showwarning("Manage Kits", "This file has no <schema> block to manage.")
+        return
+
+    if not close_editor_panel():
+        return
+
+    _take_editor_pane()
+    kits_panel = manage_kits.build_kits_panel(
+        frame_editor, on_applied=refresh_palette_kits, on_close=dismiss_kits,
+    )
+    kits_panel.frame.pack(fill=tk.BOTH, expand=True)
+    app_state.set_status("Manage Kits")
+
+
+def dismiss_kits(restore_canvas=True):
+    """Takes the Kits view down and gives the pane back."""
+    global kits_panel
+    if kits_panel is None:
+        return
+
+    kits_panel.destroy()
+    kits_panel = None
+
+    if restore_canvas:
+        _give_editor_pane_back()
+
+
 def close_editor_panel(force=False):
     """Frees the editor pane, asking about unsaved edits first. True if it is now free.
 
     Every way of leaving a panel goes through this, so "you have not saved that" is
     asked once, in one place, whether the user pressed Close, picked another sheet,
     walked the history or opened a different component. Only the Properties view has
-    anything to ask about; the Link View simply stands down.
+    anything to ask about; other views simply stand down.
     """
     if link_panel is not None:
         dismiss_link_view()
         return True
+    if kits_panel is not None:
+        dismiss_kits()
+        return True
     if properties_panel is None:
         return True
     if force:
@@ -1919,7 +1957,7 @@ menu_bar.add_cascade(label="View", menu=menu_view)
 menu_kits = tk.Menu(menu_bar, tearoff=0)
 menu_kits.add_command(
     label="Manage Kits...",
-    command=lambda: manage_kits.open_dialog(on_applied=refresh_palette_kits)
+    command=show_kits
 )
 menu_bar.add_cascade(label="Kits", menu=menu_kits)