ocs_doc_api: layer CRUD, per-curve layer assignment, XDATA/XRECORD support, and bulk SetXDataMany

crates/ocs_doc_api/bindings/README.md

@@ -21,8 +21,39 @@ The bridge converts these objects to the Rust DTOs and bincode 1.3 wire format,
 sends `DocApiRequest { tab_id, bytes }`, and decodes `Result<Receipt, ApiError>`.
 Host plugin API version 6 and document envelope version 1 are required.
 
+For Rust plugins compiled against `ocs_doc_api` with the `doc_api_host` feature,
+use the `doc_api_for_host` helper to build a typed `DocApi` from any
+`ocs_plugin_api::host::HostApi` that exposes a `PluginRequestSender`
+(out-of-process / worker-thread hosts):
+
+```rust
+use ocs_doc_api::doc_api_for_host;
+use ocs_plugin_api::host::HostApi;
+
+fn on_dispatch(host: &mut dyn HostApi) -> Option<()> {
+    let doc_api = doc_api_for_host(host)?;
+    let doc = doc_api.document(host.tab_id());
+    let cube = doc.solids().create_cuboid([0.0; 3], [10.0; 3]).ok()?;
+    // ...
+    Some(())
+}
+```
+
+In-process plugins should use `DocApi::in_process(backend, tab_id)` with a
+concrete `DocApiBackend`; `doc_api_for_host` returns `None` for hosts that do not
+expose a `PluginRequestSender`.
+
 Decode receipt outcomes as `{"NewId": 42}` or `{"NewIds": [42, 43]}` and query
 results as externally tagged dictionaries such as `{"Volume": 12.5}`. The facade
-unwraps these into typed handles or values. The bridge must raise an exception
-for an error response. Transport binding determines the tab; requesting another
-tab or combining typed handles from different documents raises an error.
+unwraps these into typed handles or values. Layer results use `{"Layers": [...]}`
+and `{"EntityLayer": "WALLS"}`. Layer properties (`LayerInfo`, `LayerFlags`,
+`Color`, `LineWeight`) appear as plain dictionaries in operation payloads, e.g.
+`{"CreateLayer": {"name": "Walls", "flags": {"frozen": false, "locked": false,
+"frozen_in_new_viewport": false, "off": false}, "color": {"Index": 7},
+"line_type": "Continuous", "line_weight": {"Default": null},
+"plot_style": "", "is_plottable": true}}`.
+XDATA and XRECORD payloads appear as nested externally tagged dictionaries
+(e.g. `{"XData": {"application_name": ..., "values": [...]}}` or
+`{"XRecord": {"name": ..., "entries": [...]}}`). The bridge must raise an
+exception for an error response. Transport binding determines the tab; requesting
+another tab or combining typed handles from different documents raises an error.