feat(automation): replay pointer events on the canvas

The new pointer op sends moves (canvas pixels, or a world point projected
through the camera the cursor edits with), button presses/releases and
wheel steps in order, and reports the cursor's world point after each, so
grip drags and picks go through the same cursor path as the mouse.
click now projects through that editing camera too (it used the model
camera inside an entered viewport), and the grips read reports each
grip's constraint axis.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

src/mcp_ops.rs

@@ -304,6 +304,22 @@ pub static CLICK: OpDef = OpDef {
     example: r#"{"op":"click","point":[10,0,0],"modifiers":"ctrl"}"#,
 };
 
+pub static POINTER: OpDef = OpDef {
+    name: "pointer",
+    doc: "Replay mouse events on the drawing canvas in order, as the mouse sends them: move to canvas pixels or to a world point (projected through the camera the cursor edits with), press and release a button, turn the wheel. A grip press-move-release goes through the same cursor path as a hand drag. Each step reports the cursor's world point.",
+    batchable: true,
+    params: &[
+        req(
+            "events",
+            Ty::ArrayOf(&Ty::Raw(r#"{"type":"object","properties":{"move":{"type":"array","items":{"type":"number"},"minItems":2,"maxItems":2},"move_world":{"type":"array","items":{"type":"number"},"minItems":3,"maxItems":3},"press":{"type":"string","enum":["left","right","middle"]},"release":{"type":"string","enum":["left","right","middle"]},"wheel":{"type":"number"}}}"#)),
+            "Events in order; each holds one of move, move_world, press, release or wheel (lines, positive zooms in).",
+        ),
+        opt("modifiers", Ty::Str, "Keys held throughout: \"ctrl\", \"shift\" or \"ctrl+shift\"."),
+    ],
+    rules: &[],
+    example: r#"{"op":"pointer","events":[{"move_world":[10,0,0]},{"press":"left"},{"release":"left"},{"move_world":[12,3,0]},{"press":"left"},{"release":"left"}]}"#,
+};
+
 pub static SET_PROPERTIES: OpDef = OpDef {
     name: "set_properties",
     doc: "Atomically update record properties by RFC 6901 JSON pointer paths.",
@@ -877,6 +893,7 @@ pub static OPS: &[&OpDef] = &[
     &PROPERTY,
     &GRIP_DRAG,
     &CLICK,
+    &POINTER,
     &SET_PROPERTIES,
     &ACTION,
     &EMBED_IMAGE,