优化原生结果编码传输与浏览器缓存，记录八路性能基线

原生结果series通过字节索引直传，C端使用Ryu精确回读编码和64 KiB批量写出；网页采用Float64缓存和CSV工作线程，减少结果处理与保存等待。

补充八路AME曲线核查、全流程分阶段计时、独立编码基准和复现工具，固定后续优化采用修正八路及rtol=1e-8。C写出1.1808→0.1638 s，点击到可查看8.0100→6.9756 s。

验证：最终10项编码专项、29项相关后端回归通过；8份原生结果逐位一致，16次网页结果/CSV/刷新恢复通过。前端构建及缓存/CSV专项在本轮结果处理工作中通过。环境、原始大结果与临时构建不纳入Git。

app/simulation/results.py

@@ -2,7 +2,10 @@
 from __future__ import annotations
 
 from dataclasses import dataclass
-from typing import Literal
+from typing import TYPE_CHECKING, Literal
+
+if TYPE_CHECKING:
+    from app.simulation.native_codegen.transport import NativeSeriesJson
 from app.simulation.core.metadata import ResultVariableMetadata
 
 SimulationRunStatus = Literal["completed", "cancelled", "failed"]
@@ -30,11 +33,15 @@ class GenericSimulationResult:
     simulated_until: float
     requested_stop_time: float
     variables: tuple[ResultVariableMetadata, ...]
-    series: dict[str, list[float]]
+    series: dict[str, list[float]] | NativeSeriesJson
     final: dict[str, float]
     diagnostics: dict[str, object]
 
-    def as_dict(self) -> dict[str, object]:
+    def as_dict(self, *, raw_series: bool = False) -> dict[str, object]:
+        from app.simulation.native_codegen.transport import NativeSeriesJson
+        series = self.series
+        if isinstance(series, NativeSeriesJson) and not raw_series:
+            series = series.materialize()
         return {
             "success": self.success,
             "status": self.status,
@@ -43,7 +50,7 @@ class GenericSimulationResult:
             "simulatedUntil": self.simulated_until,
             "requestedStopTime": self.requested_stop_time,
             "variables": [variable.as_dict() for variable in self.variables],
-            "series": self.series,
+            "series": series,
             "final": self.final,
             "diagnostics": self.diagnostics,
         }