Fix GuidedValueSlider overlapping toolbar

[Copilot]

Description

The GuidedValueSlider was anchored to parent.top without margin, causing it to render behind the toolbar.

Added anchors.topMargin: toolbar.height + _widgetMargin following the existing pattern from widgetLayer. This positions the slider below the toolbar with consistent visual spacing.

Changed:

• src/FlyView/FlyView.qml line 170: Added topMargin anchor property

GuidedValueSlider {
    id:                 guidedValueSlider
    anchors.right:      parent.right
    anchors.top:        parent.top
    anchors.bottom:     parent.bottom
    anchors.topMargin:  toolbar.height + _widgetMargin  // Added
    z:                  QGroundControl.zOrderTopMost
    visible:            false
}

Test Steps

1. Launch QGroundControl
2. Connect to a vehicle and enter FlyView
3. Trigger a guided action that displays the GuidedValueSlider (e.g., altitude change)
4. Verify slider appears below toolbar, not behind it

Checklist:

• Review Contribution Guidelines.
• Review Code of Conduct.
• I have tested my changes.

Related Issue

By submitting this pull request, I confirm that you can use, modify, copy, and redistribute this contribution, under the terms of your choice.

Original prompt

---

This section details on the original issue you should resolve

<issue_title>GuidedValueSlider goes up behind the toolbar</issue_title>
<issue_description></issue_description>

<agent_instructions>The top of the GuidedValueSlider should be anchored to the bottom of the toolbar</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes GuidedValueSlider goes up behind the toolbar #13714

---

💬 We'd love your input! Share your thoughts on Copilot coding agent in our 2 minute survey.

[Copilot]

Pull request overview

This PR fixes a UI layout bug where the GuidedValueSlider component was rendering behind the toolbar in FlyView. The fix adds a top margin calculation that accounts for the toolbar height, ensuring the slider appears below the toolbar with appropriate spacing.

• Added anchors.topMargin property to GuidedValueSlider using the established pattern toolbar.height + _widgetMargin
• This matches the existing layout pattern used by widgetLayer (line 128)
• The fix is minimal and follows QGC's QML anchoring conventions