feat: integrate SimpleCADAPI 2.0.2 CAD workflows

SimpleCADAPI/docs/core/serialization/README.md

@@ -10,14 +10,19 @@ The long-form schema reference remains [`../operation_graph_json_spec.md`](../op
 import json
 import simplecadapi as scad
 
-with scad.GraphSession() as session:
-    body = scad.make_box_rsolid(10, 6, 2)
-    hole = scad.make_cylinder_rsolid(1, 4, bottom_face_center=(0, 0, -1))
+@scad.model(graph_id="drilled_block")
+def build_model():
+    body = scad.make_box_rsolid(width=10, height=6, depth=2)
+    hole = scad.make_cylinder_rsolid(
+        radius=1, height=4, bottom_face_center=(0, 0, -1)
+    )
     result = scad.cut_rsolid(body, hole)
+    scad.capture_result(value=result)
+    return result
 
-model_json = scad.export_model_json(session)
-payload = json.loads(model_json)
-rebuilt = scad.replay_model_json(model_json)
+model = build_model()
+payload = json.loads(model.model_json)
+rebuilt = model.replay()
 ```
 
 Inspect these fields:
@@ -29,6 +34,17 @@ Inspect these fields:
 - `node["inputs"]`: upstream node ids used by replay.
 - `payload["leaf_ids"]`: explicit final result node ids.
 - `payload["expression_graph"]`: expression DAG used by expression-backed parameters.
+- `payload["tolerance_graph"]`: dimension-chain requirements and validation evidence.
+
+For new top-level models, `ModelResult.model_json` is the preferred artifact
+accessor. Use `@scad.requires_session` for reusable builders and
+`scad.capture_result(...)` when the final output should not be inferred from
+all graph leaves. If a model invocation also needs durable CAD/viewer files,
+pass `export_dir=...` to `@scad.model`; its captured geometry/product values
+then produce one self-contained `<graph_id>.scene.zip`. It embeds
+`model/model.json`, mapped project-relative Python sources, and the evaluated
+render/selection assets. It does not create adjacent model/session JSON, STEP,
+STL, or FCStd files. No files are written when `export_dir` is omitted.
 
 ## Important rule: source API is not always graph API
 
@@ -52,11 +68,13 @@ Many user-facing functions are convenience APIs. During an active `GraphSession`
 - [Primitive and profile operations](primitives-and-profiles.md)
 - [Features, booleans, transforms, patterns, and selectors](features-booleans-transforms.md)
 - [Expressions and replay behavior](expressions-and-replay.md)
+- [Physical units and dimension inference](../physical-units.md)
+- [Dimension tolerance chains](../dimension-tolerance-chains.md)
 
-## Example
+## Examples
 
-See [`../../../examples/07_serialization_operation_tree.py`](../../../examples/07_serialization_operation_tree.py). It intentionally exercises every canonical core operation and writes:
-
-- `examples/out/serialization_operation_tree.model.json`
-- `examples/out/serialization_operation_tree.summary.md`
-- `examples/out/serialization_operation_tree.step`
+The retained examples use the same model/session contract. See
+[`../../../examples/08_constrained_sketch.py`](../../../examples/08_constrained_sketch.py)
+for sketch promotion and replay, and
+[`../../../examples/10_part_assembly.py`](../../../examples/10_part_assembly.py)
+for product hierarchy and automatic artifact export.