Add ZeroFriction material and Pump object to scene

- Introduce `ZeroFriction` physics material for use in the scene.
- Add `Pump` GameObject with various components, including Rigidbody, CapsuleCollider, and MeshRenderer.
- Add configurable joint connecting `Upper` object and `Pump`.
- Update `SampleScene` with new objects and configurations for physics interactions.

Assets/ZeroFriction.physicMaterial

@@ -0,0 +1,15 @@
+%YAML 1.1
+%TAG !u! tag:unity3d.com,2011:
+--- !u!134 &13400000
+PhysicsMaterial:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_Name: ZeroFriction
+  serializedVersion: 2
+  m_DynamicFriction: 1
+  m_StaticFriction: 1
+  m_Bounciness: 0
+  m_FrictionCombine: 0
+  m_BounceCombine: 0