feat(studio+components): typed enum fields, palette prefill, generic list rows

- closed-set stringly-typed fields become real Rust enums (stepper
  orientation, chart funnel direction, cursor style and path easing —
  serde values identical; unknown strings now fail the typed parse as
  blocking validate errors instead of silent fallbacks; path_easing
  loses its silent ease_in_out catch-all, the one behavior break,
  no repo example affected; cursor_style flagged as unconsumed by the
  painter). The schema-driven inspector renders exact-variant selects
  automatically
- chart::DEFAULT_PALETTE goes pub; an empty chart colors list shows
  an 'engine palette' hint and + Add color prefills the 8 colors the
  canvas actually renders (pure palette_prefill map, extensible)
- StringList kind for non-color string arrays (axes, categories) with
  per-entry inputs; third list control triggers the rule of three:
  generic ListRows shell (render-prop items) now backs ColorRows,
  NumberList and StringList; radar_data joins the structured-data
  exclusions

Author: LeadcodeDev

crates/rustmotion-components/src/chart/funnel.rs

@@ -16,11 +16,7 @@ impl Chart {
         h: f32,
         progress: f32,
     ) -> Result<()> {
-        let horizontal = self
-            .direction
-            .as_deref()
-            .map(|d| d == "horizontal")
-            .unwrap_or(false);
+        let horizontal = self.direction == Some(super::ChartDirection::Horizontal);
 
         if horizontal {
             self.render_funnel_horizontal(canvas, w, h, progress)

crates/rustmotion-components/src/chart/mod.rs

@@ -20,10 +20,21 @@ mod radial;
 mod scatter;
 mod waterfall;
 
-pub(crate) const DEFAULT_PALETTE: &[&str] = &[
+/// The engine's default series palette. `pub` so the studio can prefill an
+/// empty `colors` list with what the canvas actually renders.
+pub const DEFAULT_PALETTE: &[&str] = &[
     "#3B82F6", "#EF4444", "#22C55E", "#F59E0B", "#8B5CF6", "#EC4899", "#06B6D4", "#F97316",
 ];
 
+/// Funnel flow direction. Closed set (painter matches both variants); JSON
+/// values unchanged ("vertical"/"horizontal").
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum ChartDirection {
+    Vertical,
+    Horizontal,
+}
+
 #[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
 #[serde(rename_all = "snake_case")]
 pub enum ChartType {
@@ -123,7 +134,7 @@ pub struct Chart {
     // Funnel direction
     /// Direction for funnel chart: "vertical" (default) or "horizontal".
     #[serde(default)]
-    pub direction: Option<String>,
+    pub direction: Option<ChartDirection>,
 
     // Axes, grid, labels
     #[serde(default)]

crates/rustmotion-components/src/cursor.rs

@@ -47,11 +47,11 @@ pub struct Cursor {
     pub click_duration: f32,
     /// Visual cursor style: "default" (arrow) or "pointer" (hand).
     /// Currently both render as a bar; this is metadata for future SVG cursors.
-    #[serde(default = "default_cursor_style")]
-    pub cursor_style: String,
+    #[serde(default)]
+    pub cursor_style: CursorStyle,
     /// Easing for movement between waypoints: "ease_in_out" (default), "linear", "ease_out".
-    #[serde(default = "default_path_easing")]
-    pub path_easing: String,
+    #[serde(default)]
+    pub path_easing: CursorPathEasing,
     #[serde(flatten)]
     pub timing: TimingConfig,
     #[serde(default)]
@@ -86,12 +86,24 @@ fn default_click_duration() -> f32 {
     0.3
 }
 
-fn default_cursor_style() -> String {
-    "default".to_string()
+/// Visual cursor style. Closed documented set; JSON values unchanged.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum CursorStyle {
+    #[default]
+    Default,
+    Pointer,
 }
 
-fn default_path_easing() -> String {
-    "ease_in_out".to_string()
+/// Easing of the cursor's waypoint path. Closed set, now matched
+/// exhaustively; previously-silent unknown values fail the typed parse.
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum CursorPathEasing {
+    Linear,
+    EaseOut,
+    #[default]
+    EaseInOut,
 }
 
 rustmotion_core::impl_traits!(Cursor {
@@ -161,11 +173,10 @@ impl Cursor {
         let raw_t = ((time - move_start) / move_duration).clamp(0.0, 1.0);
 
         // Apply easing
-        let t = match self.path_easing.as_str() {
-            "linear" => raw_t,
-            "ease_out" => 1.0 - (1.0 - raw_t).powi(3),
-            _ => {
-                // ease_in_out
+        let t = match self.path_easing {
+            CursorPathEasing::Linear => raw_t,
+            CursorPathEasing::EaseOut => 1.0 - (1.0 - raw_t).powi(3),
+            CursorPathEasing::EaseInOut => {
                 if raw_t < 0.5 {
                     4.0 * raw_t * raw_t * raw_t
                 } else {

crates/rustmotion-components/src/stepper.rs

@@ -20,8 +20,16 @@ fn default_transition_duration() -> f64 {
     0.5
 }
 
-fn default_orientation() -> String {
-    "horizontal".to_string()
+/// Layout axis of the stepper. Closed set, matched exhaustively by the
+/// painter; serde snake_case keeps the JSON values identical
+/// ("horizontal"/"vertical") — an unknown value now fails the typed parse
+/// (blocking validate error, by design).
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Default, Serialize, Deserialize, JsonSchema)]
+#[serde(rename_all = "snake_case")]
+pub enum StepperOrientation {
+    #[default]
+    Horizontal,
+    Vertical,
 }
 
 fn default_active_color() -> String {
@@ -64,8 +72,8 @@ pub struct Stepper {
     #[serde(default = "default_transition_duration")]
     pub transition_duration: f64,
     /// Layout direction: "horizontal" or "vertical".
-    #[serde(default = "default_orientation")]
-    pub orientation: String,
+    #[serde(default)]
+    pub orientation: StepperOrientation,
     /// Color of the active step node.
     #[serde(default = "default_active_color")]
     pub active_color: String,
@@ -146,7 +154,7 @@ impl Stepper {
         let emoji_desc_font =
             emoji_typeface().map(|tf| skia_safe::Font::from_typeface(tf, desc_font_size));
 
-        let is_horizontal = self.orientation == "horizontal";
+        let is_horizontal = self.orientation == StepperOrientation::Horizontal;
 
         if is_horizontal {
             let padding = r + 8.0;