ocs_doc_api: Phase 4 set_view + viewport-view query

- SetViewportView op + GetViewportView query (append-only).
- backend set_viewport_view (update Viewport.view_target/view_height) + viewport_view.
- facade Entity::set_view/viewport_view (Viewport returns Entity).
- spec Viewport methods; api_reference + binding_schema regenerated; mocks + baseline.
- Test phase4_set_view_and_view_query -> 609 host lib + 3 consistency green.
- Phase 4 complete.

crates/ocs_doc_api/src/gen/api_reference.md

@@ -158,6 +158,11 @@ Paper-space viewport: a width×height window at center looking at view_target wi
 
 - **create_viewport**(`center: [f64; 3], width: f64, height: f64, view_target: [f64; 3], view_height: f64`) -> `Entity`
 
+### Methods
+
+- **viewport_view**(``) -> `([f64; 3], f64)` — query `GetViewportView`
+- **set_view**(`view_target: [f64; 3], view_height: f64`) -> `()` — op `SetViewportView`
+
 ## `Entity` (acadrust `RasterImage`, collection `entities`)
 
 Raster image (read-mostly): GetEntity kind + coarse bounds (insertion + u*width + v*height); generic delete. No typed create in v1.

crates/ocs_doc_api/src/gen/binding_schema.json

@@ -339,7 +339,39 @@
       "acadrust_variant": "Viewport",
       "collection": "entities",
       "handle": "Entity",
-      "methods": [],
+      "methods": [
+        {
+          "args": [],
+          "bulk": false,
+          "fixed": null,
+          "kind": "query",
+          "name": "viewport_view",
+          "op": null,
+          "query": "GetViewportView",
+          "read_only": true,
+          "returns": "([f64; 3], f64)"
+        },
+        {
+          "args": [
+            {
+              "name": "view_target",
+              "ty": "[f64; 3]"
+            },
+            {
+              "name": "view_height",
+              "ty": "f64"
+            }
+          ],
+          "bulk": false,
+          "fixed": null,
+          "kind": "op",
+          "name": "set_view",
+          "op": "SetViewportView",
+          "query": null,
+          "read_only": false,
+          "returns": "()"
+        }
+      ],
       "name": "Viewport"
     },
     {

crates/ocs_doc_api/src/gen/ops_gen.rs

@@ -42,4 +42,6 @@ pub enum Operation {
     CreateDimensionLinear(DimensionSpec),
     // attributes
     SetAttribute { id: ObjectId, tag: String, value: String },
+    // viewport view
+    SetViewportView { id: ObjectId, view_target: [f64; 3], view_height: f64 },
 }

crates/ocs_doc_api/src/gen/query_gen.rs

@@ -30,4 +30,6 @@ pub enum Query {
     GetAttributes { id: ObjectId },
     /// The entity ids + kinds inside a block definition (read-only traversal).
     GetBlockEntities { block_name: String },
+    /// A viewport's view (target + zoom height).
+    GetViewportView { id: ObjectId },
 }