Add LineChartData.prevent_curve_over_shooting and LineChartData.prevent_curve_over_shooting_threshold props (#2354)

* initial commit

* reformat

Author: ndonkoHenri

package/lib/src/controls/linechart.dart

@@ -301,6 +301,10 @@ class _LineChartControlState extends State<LineChartControl> {
       for (var e in dataViewModel.dataPoints) FlSpot(e.x, e.y): e
     };
     return LineChartBarData(
+        preventCurveOverShooting:
+            dataViewModel.control.attrBool("preventCurveOverShooting", false)!,
+        preventCurveOvershootingThreshold: dataViewModel.control
+            .attrDouble("preventCurveOverShootingThreshold", 10.0)!,
         spots: dataViewModel.dataPoints.map((p) => FlSpot(p.x, p.y)).toList(),
         showingIndicators: dataViewModel.dataPoints
             .asMap()

sdk/python/packages/flet-core/src/flet_core/charts/line_chart_data.py

@@ -25,6 +25,8 @@ def __init__(
         gradient: Optional[Gradient] = None,
         stroke_width: OptionalNumber = None,
         stroke_cap_round: Optional[bool] = None,
+        prevent_curve_over_shooting: Optional[bool] = None,
+        prevent_curve_over_shooting_threshold: OptionalNumber = None,
         dash_pattern: Optional[List[int]] = None,
         shadow: Optional[BoxShadow] = None,
         above_line_bgcolor: Optional[str] = None,
@@ -54,6 +56,8 @@ def __init__(
         self.gradient = gradient
         self.stroke_width = stroke_width
         self.stroke_cap_round = stroke_cap_round
+        self.prevent_curve_over_shooting = prevent_curve_over_shooting
+        self.prevent_curve_over_shooting_threshold = prevent_curve_over_shooting_threshold
         self.shadow = shadow
         self.dash_pattern = dash_pattern
         self.above_line_bgcolor = above_line_bgcolor
@@ -141,6 +145,26 @@ def stroke_cap_round(self) -> Optional[bool]:
     def stroke_cap_round(self, value: Optional[bool]):
         self._set_attr("strokeCapRound", value)
 
+    # prevent_curve_over_shooting
+    @property
+    def prevent_curve_over_shooting(self) -> Optional[bool]:
+        return self._get_attr(
+            "preventCurveOverShooting", data_type="bool", def_value=False
+        )
+
+    @prevent_curve_over_shooting.setter
+    def prevent_curve_over_shooting(self, value: Optional[bool]):
+        self._set_attr("preventCurveOverShooting", value)
+
+    # prevent_curve_over_shooting_threshold
+    @property
+    def prevent_curve_over_shooting_threshold(self) -> OptionalNumber:
+        return self._get_attr("preventCurveOverShootingThreshold", data_type="float")
+
+    @prevent_curve_over_shooting_threshold.setter
+    def prevent_curve_over_shooting_threshold(self, value: OptionalNumber):
+        self._set_attr("preventCurveOverShootingThreshold", value)
+
     # dash_pattern
     @property
     def dash_pattern(self):