refactor(reaction): refactored to an abstract reaction class in prep for weak reactions

src/include/gridfire/interfaces/solver/solver_interfaces.h

@@ -0,0 +1,11 @@
+#pragma once
+
+#include "fourdst/plugin/plugin.h"
+
+class SolverPluginInterface : public fourdst::plugin::PluginBase {
+public:
+    using PluginBase::PluginBase;
+
+    ~SolverPluginInterface() override = default;
+    virtual void log_time(double t, double dt) = 0;
+};