More work on toolbar transparency

[DonLakeFlyer]

• ToolStrip is now transparent as well
• Transparency respects Palette Themes

[Copilot]

Pull Request Overview

This PR enhances toolbar transparency support by extending it to ToolStrip components and ensuring transparency properly respects palette themes.

• Introduces new transparent color properties windowTransparent and windowTransparentText to the QGC palette system
• Updates all toolbar indicators to use the new transparent text color instead of toolbarText
• Makes ToolStrip components transparent and removes deprecated properties

Reviewed Changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
src/QmlControls/QGCPalette.h	Adds new transparent color properties and removes unused ones
src/QmlControls/QGCPalette.cc	Defines transparent color values and removes deprecated single colors
src/QmlControls/ToolStrip.qml	Makes ToolStrip background transparent and removes title property
src/QmlControls/ToolStripHoverButton.qml	Updates button to use transparent colors and removes background
src/QmlControls/FlyViewToolBar.qml	Implements transparent toolbar with gradient background
src/QmlControls/FlyViewToolBarIndicators.qml	Removes background container to support transparency
Multiple indicator files	Updates text colors to use new transparent text color

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[Copilot]

The anchors.fill: parent property was removed but the Rectangle still needs proper positioning. Consider adding explicit positioning or verify this Rectangle is properly sized without anchors.