⚡ Adds event bus

esp32/include/event_bus/event_metadata.h

@@ -0,0 +1,16 @@
+#pragma once
+#include <event_bus/event_types.h>
+#include <cstdint>
+
+struct EventMetadata {
+    EventType type;
+    uint64_t timestamp;
+    uint32_t sequence;
+    const char* source;
+};
+
+template <typename Msg>
+struct EventEnvelope {
+    EventMetadata metadata;
+    Msg payload;
+};