frontend(tkinter): add clickable link to tuning guide in step 11 dialog

When transitioning from Step 11 (initial ATC PID tuning) to Step 12,
if "Automatically open documentation links..." is disabled, the popup
message previously mentioned the tuning guide but did not provide any
clickable links, which was confusing to users.

This change adds a blue, underlined "Open Tuning Guide" label that
opens the relevant ArduPilot tuning instructions page in the default
web browser

Author: neo-0007

ardupilot_methodic_configurator/frontend_tkinter_parameter_editor.py

@@ -541,6 +541,17 @@ def __should_copy_fc_values_to_file(self, selected_file: str) -> None:  # pylint
             message_label = tk.Label(dialog, text=msg, justify=tk.LEFT, padx=20, pady=10)
             message_label.pack(padx=10, pady=10)
 
+            # Clickable link to tuning guide
+            link_label = tk.Label(
+                dialog,
+                text=_("Open Tuning Guide"),
+                fg="blue",
+                cursor="hand2",
+                font=("TkDefaultFont", 9, "underline"),
+            )
+            link_label.pack(pady=(0, 10))
+            link_label.bind("<Button-1>", lambda e: webbrowser_open("https://ardupilot.github.io/MethodicConfigurator/TUNING_GUIDE_ArduCopter#68-initial-attitude-pid-gains-vehicle-size-dependent"))
+
             # Result variable
             result: list[Optional[Literal[True, False]]] = [None]