Close RPC console autocomplete when changing desktop tabs

[johnny9]

Problem

In the desktop wallet view, enter a partial RPC command such as getblock to open the console autocomplete popup, then select another top-level tab. The popup remains visible above the newly selected view.

DesktopWallets keeps CommandConsole alive as a StackLayout child. The autocomplete is a Popup, whose current dismissal paths are Escape, focus loss, and input changes; switching the top-level tab does not notify the console that it was left.

Steps to reproduce

1. Start the desktop wallet view and select the Console tab.
2. Type a command prefix with available matches, for example getblock.
3. Confirm the autocomplete popup is open.
4. Select Activity, Settings, or another top-level tab.

Actual: The autocomplete popup remains visible over the selected tab.

Expected: The popup closes when leaving the Console tab.

Proposed fix

Expose tab changes through the common navigation bar API. The signal should carry the previous and newly selected tab controls, e.g. tabChanged(previousTab, currentTab), so a child view can react to leaving its own tab without depending on a numeric index.

CommandConsole can receive its associated navigation tab and call autocompletePopup.close() when previousTab is that tab. This keeps transient-UI cleanup local to the owning view while providing a reusable tab-transition hook for other persistent desktop views.

Test coverage

Add a QML regression test that opens consoleAutocompletePopup, switches from Console to another desktop tab, and verifies the popup is no longer visible.

A proposed implementation is available on johnny9:fix/console-autocomplete-tab-switch.

[uqlidi]

I read the proposed solution (johnny9@6c4970e) and I see the idea is right, the view should dismiss its own popup when its tab is left, keyed off the tab ButtonGroup, not StackLayout visibility (I tried onVisibleChanged; it never fires the needed edge).

I'd just simplify the wiring. Instead of adding a tabChanged signal to NavigationBar2 (a generic layout) and passing two refs into the console, the console only needs one bound boolean:

• CommandConsole gets property bool tabActive: true and closes the popup when it goes false.
• DesktopWallets binds tabActive: consoleTabButton.checked.

Take a look at #809, please