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/main.py

@@ -1151,7 +1151,8 @@ def build_reactflow_system_xml(project: ReactFlowProjectPayload) -> bytes:
             edge.targetHandle,
             edge.id,
         )
-        validate_compatible_ports(first, second, edge.id)
+        validate_compatible_ports(first, second, edge.id,
+                                  f"{edge.source}.{first.name}", f"{edge.target}.{second.name}")
 
         connection_node = ET.SubElement(
             connections_node,
@@ -1203,11 +1204,18 @@ def validate_compatible_ports(
     first: "PortDefinition",
     second: "PortDefinition",
     connection_id: str,
+    first_label: str | None = None,
+    second_label: str | None = None,
 ) -> None:
+    from app.simulation.core.port_computation import PortSupplyError, port_supply_issue
+
     if first.kind != second.kind:
         raise ValueError(f"Connection {connection_id} mixes physical and signal ports.")
     if first.domain != second.domain:
         raise ValueError(f"Connection {connection_id} connects incompatible domains.")
+    supply_issue = port_supply_issue(first, second, first_label, second_label)
+    if supply_issue:
+        raise PortSupplyError(supply_issue)
     if first.kind == "signal" and {first.nominal_role, second.nominal_role} != {
         "input",
         "output",
@@ -1422,6 +1430,7 @@ def _compile_solver_network(
             edge.endpoint_b_port,
             connection_id=edge.id,
         )
+    network.validate_port_supplies()
     return network