docs(native-charts): add chapter for native gauge chart

docs/components/charts/native-gauge-chart.md

@@ -0,0 +1,39 @@
+# Native gauge chart
+
+**Native gauge charts** are lightweight data visualization elements that represent one or more values as a position on a radial arc scale. Unlike the [ECharts-based gauge chart](gauge-chart.md), they require no third-party charting library, making them ideal for performance-sensitive or bundle-size-constrained applications.
+
+## Usage ---
+
+T.B.D
+
+## Design ---
+
+T.B.D
+
+## Code ---
+
+### Usage
+
+```ts
+import { SiNChartGaugeComponent } from '@siemens/native-charts-ng/gauge';
+
+@Component({
+  imports: [SiNChartGaugeComponent, ...]
+})
+```
+
+### Sum mode
+
+Multiple series arcs are stacked on the gauge ring. The center shows their combined total.
+
+<si-docs-component example="si-ncharts/si-nchart-gauge" height="400"></si-docs-component>
+
+### Single mode
+
+A single arc covers the ring. Colored background segments can be layered beneath the arc to indicate qualitative ranges.
+
+<si-docs-component example="si-ncharts/si-nchart-gauge-single" height="400"></si-docs-component>
+
+<si-docs-api component="SiNChartGaugeComponent" package="@siemens/native-charts-ng" hideImplicitlyPublic="true"></si-docs-api>
+
+<si-docs-types></si-docs-types>

mkdocs.yml

@@ -177,6 +177,7 @@ nav:
       - Scatter chart:                    'components/charts/scatter-chart.md'
       - Generic chart:                    'components/charts/generic-chart.md'
       - Micro charts:                     'components/charts/micro-charts.md'
+      - Native gauge chart:               'components/charts/native-gauge-chart.md'
     - Maps:                               'components/maps/maps.md'
     - Pages:
       - About:                            'components/pages/about.md'