feat(solver-bootstrap): step 3 — core-ids-and-diagnostics

include/fesa/core/diagnostic.hpp

@@ -0,0 +1,31 @@
+#pragma once
+
+#include <optional>
+#include <string>
+
+#include <fesa/core/source_location.hpp>
+
+namespace fesa {
+
+enum class DiagnosticStage {
+    io,
+    syntax,
+    semantic,
+    model,
+    equation,
+    solver,
+    results,
+    validation
+};
+
+enum class Severity { warning, error };
+
+struct Diagnostic final {
+    DiagnosticStage stage;
+    Severity severity;
+    std::string code;
+    std::string message;
+    std::optional<SourceLocation> source;
+};
+
+}  // namespace fesa