前端进度条性能优化、仿真结束后后处理优化；后端C代码生成流程优化：先识别来源，再按照已知未知量需求排序，最后局部求解

app/simulation/components/experimental/flow/resistive_pipe.py

@@ -7,12 +7,13 @@ from app.simulation.core.catalog import ComponentDisplaySpec, PortDisplaySpec
 from app.simulation.core.metadata import ParameterDefinition
 from app.simulation.core.medium import IdealGasMedium
 from app.simulation.core.ports import PortDefinition
+from app.simulation.core.port_computation import FLOW_SUPPLY
 
 class ResistivePipe(AlgebraicComponent):
     """Quasi-steady Darcy resistance used by topology-driven simulation."""
     MODEL_TYPE = 'pipe'
     MODEL_VERSION = '1.0.0'
-    PORTS = (PortDefinition.pneumatic('port_a', nominal_role='inlet'), PortDefinition.pneumatic('port_b', nominal_role='outlet'))
+    PORTS = (PortDefinition.pneumatic('port_a', nominal_role='inlet', computation=FLOW_SUPPLY), PortDefinition.pneumatic('port_b', nominal_role='outlet', computation=FLOW_SUPPLY))
     PARAMETERS = (ParameterDefinition('length', 5.0, label='长度', quantity='length', unit='m', minimum=0.0, minimum_exclusive=True), ParameterDefinition('diameter', 0.02, label='直径', quantity='length', unit='m', minimum=0.0, minimum_exclusive=True), ParameterDefinition('lambda_darcy', 0.02, label='摩阻系数', minimum=0.0), ParameterDefinition('p0', 100000.0, label='初始压力', quantity='pressure', unit='Pa', minimum=0.0, minimum_exclusive=True), ParameterDefinition('T0', 300.0, label='初始温度', quantity='temperature', unit='K', minimum=0.0, minimum_exclusive=True))
     RESULT_VARIABLES = ()
     DISPLAY = ComponentDisplaySpec(label='管段', library_id='experimental', category_id='flow', symbol='pipe', ports=(PortDisplaySpec('port_a', 'left', order=10), PortDisplaySpec('port_b', 'right', order=20)), order=30)