ocs_doc_api: Phase 0 + Phase 2a (sweep profiles, non-solid transform, full 2D curves)

Phase 0 (outstanding supported-family methods):
- add_vertex on LwPolyline (insert vertex, out-of-range validation).
- extrude / revolve from profiles (entity_to_profile_curves: Line/Circle/Arc/
  LwPolyline straight-segment conversion -> geom2d::Curve -> brep::extrude/revolve).
- non-solid transform + transform_many via acadrust geometry
  (transform_entity_geometry for Line/Circle/Arc/Point/LwPolyline).
- ensure_transformable broadened accordingly (all-or-nothing pre-validation).

Phase 2a (full 2D curve families): ArcCurve/Ellipse/Spline/Ray/XLine.
- Curve2Spec extended (Arc/Ellipse/Spline/Ray/XLine) + create_arc/create_ellipse/
  create_spline/create_ray/create_xline facade constructors + handle types.
- entity_kind_name, entity_bounds (Arc coarse, Ellipse major-axis, Spline bbox;
  Ray/XLine unbounded), transform_entity_geometry, ensure_transformable extended.
- spec/entities.toml families; api_reference.md + binding_schema.json regenerated.

Tests: +6 doc_api integration tests (phase0_*, phase2_*) -> 598 host lib green.
IMPLEMENTATION.md updated (Phase 0 done, Phase 2a done / 2b remaining).

crates/ocs_doc_api/src/gen/api_reference.md

@@ -16,8 +16,8 @@ B-rep solid. Host resolves bodies via the solid_models cache (lift-on-miss from
 - **create_cone**(`base: [f64; 3], radius: f64, height: f64`) -> `Solid`
 - **create_torus**(`centre: [f64; 3], major_radius: f64, minor_radius: f64`) -> `Solid`
 - **create_wedge**(`origin: [f64; 3], size: [f64; 3]`) -> `Solid`
-- **extrude**(`profile: EntityRef, direction: [f64; 3]`) -> `Solid` — **not yet supported** (returns `ApiError::Unsupported`)
-- **revolve**(`profile: EntityRef, pivot: [f64; 3], axis: [f64; 3], angle: f64`) -> `Solid` — **not yet supported** (returns `ApiError::Unsupported`)
+- **extrude**(`profile: EntityRef, direction: [f64; 3]`) -> `Solid`
+- **revolve**(`profile: EntityRef, pivot: [f64; 3], axis: [f64; 3], angle: f64`) -> `Solid`
 
 ### Methods
 
@@ -48,7 +48,7 @@ B-rep solid. Host resolves bodies via the solid_models cache (lift-on-miss from
 
 ### Methods
 
-- **add_vertex**(`at: usize, point: [f64; 3]`) -> `()` — op `AddVertex` — **not yet supported** (returns `ApiError::Unsupported`)
+- **add_vertex**(`at: usize, point: [f64; 3]`) -> `()` — op `AddVertex`
 
 ## `Point` (acadrust `Point`, collection `curves`)
 
@@ -57,6 +57,36 @@ B-rep solid. Host resolves bodies via the solid_models cache (lift-on-miss from
 - **create_point**(`position: [f64; 3]`) -> `Point`
 - **create_points**(`positions: &[[f64; 3]]`) -> `Vec<Point>` *(bulk op)*
 
+## `ArcCurve` (acadrust `Arc`, collection `curves`)
+
+### Constructors (`doc.curves()`)
+
+- **create_arc**(`centre: [f64; 3], radius: f64, start_angle: f64, end_angle: f64`) -> `ArcCurve`
+
+## `Ellipse` (acadrust `Ellipse`, collection `curves`)
+
+### Constructors (`doc.curves()`)
+
+- **create_ellipse**(`centre: [f64; 3], major_axis: [f64; 3], ratio: f64, start: f64, end: f64`) -> `Ellipse`
+
+## `Spline` (acadrust `Spline`, collection `curves`)
+
+### Constructors (`doc.curves()`)
+
+- **create_spline**(`degree: i32, control_points: &[[f64; 3]], knots: &[f64], weights: &[f64]`) -> `Spline`
+
+## `Ray` (acadrust `Ray`, collection `curves`)
+
+### Constructors (`doc.curves()`)
+
+- **create_ray**(`origin: [f64; 3], direction: [f64; 3]`) -> `Ray`
+
+## `XLine` (acadrust `XLine`, collection `curves`)
+
+### Constructors (`doc.curves()`)
+
+- **create_xline**(`origin: [f64; 3], direction: [f64; 3]`) -> `XLine`
+
 ## Generic methods (every handle)
 
 Every typed handle (`Solid`, `Line`, `Circle`, `Polyline`, `Point`, `Entity`) is a