Patches applied to vendored submodules

`0001-tachyon-packet-layer-hook.patch` → `vendor/LiteNetLibPP`

Applies to: LiteNetLibPP @ c6625b0652c5930046b75b495db314456c8bc411 (https://github.com/Revan600/LiteNetLibPP), the pinned submodule under vendor/LiteNetLibPP.

Why

Upstream has no packet-layer abstraction, but the Rec Room client wraps every datagram in a trailing-marker "encrypt" layer (a 0x11 byte on the plaintext path). This patch adds a generic datagram-transform hook — the equivalent of the C# LiteNetLib PacketLayerBase — so Tachyon can install the marker without forking the library wholesale. It is deliberately generic (not RecRoom-specific) so it could be submitted upstream unchanged.

What it changes

include/lnl/net_manager.h — two public std::function members, outbound_layer and inbound_layer (both default null → stock behaviour), plus <functional>/<vector> includes.
src/lnl/net_manager.cpp
- send_raw() — if outbound_layer is set, transform the bytes just before sendto.
- receive_logic() — if inbound_layer is set, transform/drop each datagram just after recvfrom, before on_message_received.

Tachyon installs the 0x11 marker through these hooks in src/main.cpp.

How it is applied

The top-level CMakeLists.txt applies this patch to the submodule working tree at configure time, idempotently (git apply --reverse --check detects an already-patched tree and skips). This leaves the submodule showing as "dirty" in git status — that is expected. To reset it: git -C vendor/LiteNetLibPP checkout .

Regenerating the patch (if the pin is bumped)

# from a pristine checkout of the new upstream commit, with the two files edited:
git -C <litenetlibpp> diff > patches/0001-tachyon-packet-layer-hook.patch

Known limitation

The outbound hook appends its marker after LiteNetLibPP's MTU/fragmentation math, without reserving space the way the C# ExtraPacketSizeForLayer did. Safe here because every packet the server sends is far below the MTU; revisit if the server ever sends reliable data near the MTU.

README.md