Record the first unreadable packet to a file instead of logging every one

[u9g]

On a server whose particle registry does not match the client's (Jartex's lobby sends 1.21.3 ids to a 1.21.4 client, so item_slime arrives as trail with no payload), every such packet printed a full PartialReadError stack. One bot logged 14,814 of them, most of a 30 MB log, and none of them carried the bytes.

Why the bytes were never available

protodef's FullPacketParser._transform swallows partial reads: console.log(e.stack), then cb() with nothing emitted and no buffer attached. bot.on('error') never sees these. The only place the packet buffer is still in hand is parsePacketBuffer, so the daemon wraps that on each deserializer.

What it does now

The first unreadable packet is written to bad-packet.json in the daemon's working directory, then nothing else is written or printed:

{
  "bot":     { "name", "host", "port", "username", "version" },
  "state":   "play",
  "packet":  { "id": 42, "name": "world_particles" },
  "problem": "partial-read",
  "length":  51,
  "sha256":  "...",
  "bytes":   "<hex of the whole packet>",
  "error":   { "name": "PartialReadError", "message", "stack" }
}

problem is partial-read when the definitions expect more bytes than arrived, or trailing-bytes (with read) when they stop short of the end. The second case parses "successfully" and is otherwise invisible; it is the mirror image of the same registry mismatch.

At most one file: a process flag stops retries, and the file is opened with wx, so a restart in the same directory leaves the first one in place. noErrorLogging is set on the deserializer instance rather than via hideErrors, which would also mute mineflayer's _warn. nmp builds a fresh deserializer per protocol state, so the wrap is reapplied on 'state'.

Testing

Against the same minecraft-protocol / protodef@1.19.0 / minecraft-data 3.116.0-allprs build the affected bot ran, with a world_particles/trail packet truncated to the Jartex shape:

• an unwrapped deserializer prints the stack; the wrapped one prints nothing
• one file, with problem: partial-read, packet: world_particles 0x2a, the exact 51 bytes and matching sha256
• second and third bad packets: no write, file unchanged
• 'state' event: the replacement deserializer is wrapped
• a valid packet writes nothing; the same packet plus 3 stray bytes writes trailing-bytes with read: 77 of 80
• a fresh process in the same directory: no callback, first file untouched

npx tsc --noEmit reports only the pre-existing createHuman error from this checkout's stale node_modules.