fix(surface): keep a press on a window from raising a window below it - #1581

Please address the comments from this code review:

## Individual Comments

### Comment 1
<location path="src/core/qml/TitleBar.qml" line_range="146" />
<code_context>
                     onClicked: {
+                        // A covered title bar can be reached through an area of the
+                        // window above that owns no input; its buttons stay inert then.
+                        if (!surface.isTopmostWindowUnderCursor())
+                            return
                         surface.minimize()
</code_context>
<issue_to_address>
**Covered buttons still activate**

When a press starts on a covered part of a lower window’s title-bar button and ends on an exposed part of that same button, `onClicked` checks only the release-time position and does not record ownership on press, so the lower window’s button action runs even though the press began on the window above; the lower window is minimized, maximized, or closed.

Record whether the button belongs to the topmost window when pressed, and run its action only if it did.

Also at `src/core/qml/TitleBar.qml:165-166`, `src/core/qml/TitleBar.qml:191`.
</issue_to_address>

### Comment 2
<location path="src/core/qml/TitleBar.qml" line_range="146" />
<code_context>
                     onClicked: {
+                        // A covered title bar can be reached through an area of the
+                        // window above that owns no input; its buttons stay inert then.
+                        if (!surface.isTopmostWindowUnderCursor())
+                            return
                         surface.minimize()
</code_context>
<issue_to_address>
**Valid actions use the wrong position**

When a touchscreen press reaches a title-bar button or resize border while the seat cursor remains elsewhere, or a secondary-seat pointer is at a different position from the primary-seat pointer, the `TitleBar.qml` handlers call `isTopmostWindowUnderCursor()`, which checks the primary seat’s cursor instead of the touch position or the invoking seat’s pointer position, so valid actions are suppressed or actions on covered windows are allowed.

Check topmost-window status using the event position and the seat that received the event.

Also at `src/core/qml/TitleBar.qml:165`, `src/core/qml/TitleBar.qml:191`, `src/core/qml/Decoration.qml:62`, `src/surface/surfacewrapper.cpp:995-1003`.
</issue_to_address>

### Comment 3
<location path="src/surface/surfacewrapper.cpp" line_range="987" />
<code_context>
+            continue;
+        if (window->type() != Type::XdgToplevel && window->type() != Type::XWayland)
+            continue;
+        if (window->mapRectToScene(QRectF(QPointF(0, 0), window->size())).contains(scenePos))
+            return false;
+    }
</code_context>
<issue_to_address>
**Shadow presses still raise lower windows**

When the press lands in a visible shadow band outside the upper window’s bounds, `isTopmostWindowAt()` checks only the upper wrapper’s `size()`, so a press in its visible XdgShadow band falls through the coverage test and the lower window is activated and raised.

Include the upper window’s visible shadow extents in the coverage test, or hit-test its rendered shadow shape.
</issue_to_address>

### Comment 4
<location path="src/core/qml/TitleBar.qml" line_range="99-100" />
<code_context>
+        onPressAndHold: function (mouse) {
+            // Touch screen only, and never mid-drag: this timer is not stopped by
+            // movement, while a dragged window keeps the cursor over the same spot.
+            if (pressBelongsToWindow && pressWasTouch && !movingWindow)
+                surface.windowMenuRequested(Qt.point(mouse.x, mouse.y))
+        }
     }
</code_context>
<issue_to_address>
**Touch long press activates window**

When a touch long press opens the menu on an inactive window and the finger is released, `onPressAndHold` opens the window menu, but releasing the same left-button press still reaches `onClicked`, which activates the surface. Long-pressing an inactive window therefore also focuses and raises it when the menu is invoked.

Track that the press-and-hold handler ran and suppress the corresponding click action on release.

Also at `src/core/qml/TitleBar.qml:89`.
</issue_to_address>