feat(linear-static-3d-euler-beam): step 17 - parallel-for-tbb

include/fesa/assembly/parallel_for.hpp

@@ -0,0 +1,32 @@
+#pragma once
+
+#include <cstddef>
+#include <functional>
+
+namespace fesa {
+
+// Executes independent index-addressed work without exposing the backend.
+// Callers own output storage and must confine each invocation to its index.
+class ParallelFor {
+public:
+    virtual ~ParallelFor() = default;
+    virtual void execute(
+        std::size_t count,
+        const std::function<void(std::size_t)>& body) const = 0;
+};
+
+class SerialParallelFor final : public ParallelFor {
+public:
+    void execute(
+        std::size_t count,
+        const std::function<void(std::size_t)>& body) const override;
+};
+
+class TbbParallelFor final : public ParallelFor {
+public:
+    void execute(
+        std::size_t count,
+        const std::function<void(std::size_t)>& body) const override;
+};
+
+} // namespace fesa