Let the widgets use Macro Deck's border

[PyFlat-JR]

What does this PR do?

Lets both widgets use the border Macro Deck draws around a widget.

• Macro Deck already draws the border for every widget type from the border key in the widget's stored data (static, heartbeat, breathing, blink, comet, marching ants, hue shift, RGB, with an optional colour). The plugin just never let users set it.
• The Appearance tab now ends with Macro Deck's own border fields (UiWidgetAppearance.Section with Border), already translated.
• The data schema allows border; with additionalProperties: false it rejected the key before.
• The config view gets the stored widget data instead of only its flows, so the section can show the current border.
• The visibility test now resolves a condition inside an object scope (the border colour depends on border.style).

Checklist

• I have read AGENTS.md and CONTRIBUTING.md.
• dotnet build and dotnet test pass locally (0 warnings, 251 tests).
• I updated README.md / AGENTS.md if this changes what they describe.
• If this touches a device backend: I tested it against the real hardware (see below).

Device/hardware tested against (if applicable)

Not a device backend. Tested in Macro Deck on Windows: the border styles and colour show on the tile.