Shapes and timeline: toolbar Fill / Stroke edit selected shape layers; Alt+Shift+P reveals; click below layers deselects (#205)

- With a shape layer selected, the toolbar shows its Fill, Stroke and
  Stroke Width (with any tool) and editing them changes the layer's
  fills and strokes, as in After Effects (new shape.fillStroke, one
  undo step per picker or drag). Shapes drawn without a stroke get one
  when a stroke colour or width is set, so changing the stroke now works.
- Alt+Shift+P (A, S, R, T) reveals the property it keyed on each layer.
- A click in the time graph below the last layer deselects the layers
  (it only deselected keyframes), so a shape tool draws a new shape
  layer instead of a mask on the selected image.

Tests: toolbar_fill_and_stroke_paint_selected_shape_layers,
toolbar_stroke_edits_the_selected_shape_layer,
add_position_key_reveals_position,
clicking_below_the_layers_deselects_them.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018gnTnH3Jmk5zr4tMq1Mc9f

crates/engine/src/tests.rs

@@ -183,6 +183,40 @@ fn text_shape_mask_matte_parent() {
     assert_eq!(info["layers"].as_array().unwrap().len(), 2);
 }
 
+/// The toolbar's Fill / Stroke change a selected shape layer's paint (#205): a shape drawn
+/// without a stroke gets one, later edits change it, and the Contents "Add:" items (#206) include
+/// an empty Path and a Gradient Stroke that render.
+#[test]
+fn toolbar_fill_and_stroke_paint_selected_shape_layers() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"width": 400, "height": 300, "duration": 2})).unwrap();
+    let sh = s.execute("layer.newShape", json!({"kind": "rect", "fill": "#ff0000"})).unwrap()["layer"].as_u64().unwrap();
+    let paint = |s: &mut Session| s.execute("shape.fillStroke", json!({})).unwrap();
+    assert_eq!(paint(&mut s)["stroke"], serde_json::Value::Null, "drawn without a stroke");
+    s.execute("shape.fillStroke", json!({"stroke": "#00ff00", "strokeWidth": 6})).unwrap();
+    let p = paint(&mut s);
+    assert_eq!((p["stroke"][1].as_f64(), p["strokeWidth"].as_f64()), (Some(1.0), Some(6.0)), "{p}");
+    s.execute("shape.fillStroke", json!({"fill": "#0000ff", "strokeWidth": 3})).unwrap();
+    let p = paint(&mut s);
+    assert_eq!((p["fill"][2].as_f64(), p["strokeWidth"].as_f64()), (Some(1.0), Some(3.0)), "{p}");
+    // One stroke, before the fill (paths, stroke, fill), and each change is one undo step.
+    let l = s.active_comp().unwrap().layer(effectcraft_project::LayerId(sh)).unwrap().clone();
+    let group = l.props.group("contents/group").unwrap();
+    let order: Vec<&str> = group.sub("contents").unwrap().groups().map(|g| g.match_id.as_str()).collect();
+    assert_eq!(order, ["rect", "stroke", "fill"]);
+    s.execute("edit.undo", json!({})).unwrap();
+    assert_eq!(paint(&mut s)["strokeWidth"].as_f64(), Some(6.0));
+    // Only shape layers.
+    s.execute("layer.newSolid", json!({"color": "#808080"})).unwrap();
+    assert!(s.execute("shape.fillStroke", json!({"fill": "#ffffff"})).is_err());
+    for kind in ["path", "gstroke"] {
+        let r = s.execute("layer.addShapeItem", json!({"layer": sh, "kind": kind})).unwrap();
+        assert!(r["path"].as_str().is_some_and(|p| p.starts_with("contents/")), "{r}");
+    }
+    let cid = s.active_comp_id().unwrap();
+    let _ = s.render(cid, s.time(), Default::default());
+}
+
 #[test]
 fn save_and_open_roundtrip() {
     let mut s = demo();