feat: add knowledge-driven joint design studio

backend/knowledge/relations/meshes/external_cylindrical.json

@@ -0,0 +1,26 @@
+{
+  "schema_version": "1.0",
+  "id": "relation.mesh.external_cylindrical",
+  "version": "1.0.0",
+  "relation_type": "external_mesh",
+  "endpoint_rules": {
+    "source_port": "port.mesh.external_cylindrical",
+    "target_port": "port.mesh.external_cylindrical",
+    "axis_relation": "parallel"
+  },
+  "constraint_rules": [
+    "equal_module",
+    "equal_pressure_angle",
+    "equal_tooth_form",
+    "spur_or_opposite_helical_hand",
+    "center_distance_equals_pitch_radius_sum"
+  ],
+  "kinematic_effect": {
+    "equation": "(omega_source-omega_carrier)*z_source + (omega_target-omega_carrier)*z_target = 0"
+  },
+  "capability_refs": [
+    "capability.kinematics.graph",
+    "capability.validation.external_mesh"
+  ],
+  "maturity": "production"
+}

backend/knowledge/relations/meshes/internal_cylindrical.json

@@ -0,0 +1,26 @@
+{
+  "schema_version": "1.0",
+  "id": "relation.mesh.internal_cylindrical",
+  "version": "1.0.0",
+  "relation_type": "internal_mesh",
+  "endpoint_rules": {
+    "source_port": "port.mesh.internal_cylindrical",
+    "target_port": "port.mesh.external_cylindrical",
+    "axis_relation": "parallel"
+  },
+  "constraint_rules": [
+    "equal_module",
+    "equal_pressure_angle",
+    "equal_tooth_form",
+    "spur_or_same_helical_hand",
+    "center_distance_equals_pitch_radius_difference"
+  ],
+  "kinematic_effect": {
+    "equation": "(omega_source-omega_carrier)*z_source - (omega_target-omega_carrier)*z_target = 0"
+  },
+  "capability_refs": [
+    "capability.kinematics.graph",
+    "capability.validation.internal_mesh"
+  ],
+  "maturity": "production"
+}