added docs to packet struct

include/packet.h

@@ -1,6 +1,22 @@
 #pragma once
 #include <stdint.h>
 
+/*
+This is the struct that gets packed and then sent over LoRa.
+
+It's packed and uses stdint types because different hardware or compilers may attempt to
+optimize it or change the size of different things, completely stuffing up and corrupting
+our data. Endianess also matters.
+
+Version 1:
+    Message Types:
+        - message: send a message via plain text to someone
+        - hello: announce yourself to other nodes, payload should include:
+            bytes 1-4: node id
+            byte 5: battery level or 255 for unkown
+            byte 6: name length
+            continuing bytes: name
+*/
 typedef struct {
     uint8_t version;           // version number to prevent breaking older packet formats
     uint8_t ttl;               // the number of hops left in the lifespan of the packet, prevents infinite hopping