ocs_doc_api: Phase 5-ii — typed Table create

- CreateTable(TableSpec{insertion_point, data[row][col]}) op (append-only).
- backend add_table via Table::new(insertion_point, rows, cols) + set_cell_text
  (Table::default() pre-creates 3x3, so use Table::new for exact dims).
- executor validates non-empty rectangular grid; facade create_table.
- spec Table constructor; api_reference + binding_schema regenerated; mocks + baseline.
- Test phase5ii_create_table_from_grid (3x2 grid, non-rectangular rejected)
  -> 615 host lib + 3 consistency green. Phase 5 complete.

crates/ocs_doc_api/tests/mock_backend.rs

@@ -146,6 +146,13 @@ impl DocApiBackend for MockBackend {
         }
         Ok(self.alloc("AttributeDefinition"))
     }
+    fn add_table(&mut self, spec: &ocs_doc_api::ops::TableSpec) -> ApiResult<ObjectId> {
+        let cols = spec.data.first().map(|r| r.len()).unwrap_or(0);
+        if spec.data.is_empty() || cols == 0 || spec.data.iter().any(|r| r.len() != cols) {
+            return Err(ApiError::validation("CreateTable", "table needs a non-empty rectangular grid"));
+        }
+        Ok(self.alloc("Table"))
+    }
     fn set_attribute(&mut self, id: ObjectId, tag: &str, value: &str) -> ApiResult<()> {
         if !self.entity_exists(id) {
             return Err(ApiError::UnknownId(id));

crates/ocs_doc_api/tests/spec_wire_consistency.rs

@@ -70,6 +70,7 @@ fn operation_variants() -> Vec<String> {
         Operation::CreateAttributeDefinition(ocs_doc_api::ops::AttributeDefinitionSpec {
             tag: String::new(), prompt: String::new(), default_value: String::new(), insertion_point: [0.0; 3], height: 0.0, rotation: 0.0,
         }),
+        Operation::CreateTable(ocs_doc_api::ops::TableSpec { insertion_point: [0.0; 3], data: vec![] }),
     ];
     // Derive the variant names by serializing a probe of each and reading the
     // bincode variant index -> name map is not available; instead match by
@@ -163,6 +164,7 @@ const OPERATION_BASELINE: &[&str] = &[
     "CreateDimensionDiameter",
     "CreateDimensionAngular",
     "CreateAttributeDefinition",
+    "CreateTable",
 ];
 
 /// Recorded baseline of the `Query` variant order.