Move RIO hardware + firmware archive to the TeslaRel410 repo

The physical RIO board docs (photos, schematics, GAL decode) and the
board firmware (dumps, disassembly, make_patch.py, RIO 4.3 + FastRIO
images, analysis, testlogs) describe hardware shared across all Tesla
cockpits with a lifecycle independent of this Windows app — a
native-game-only cabinet runs the firmware and never touches RIOjoy.
They now live in TeslaRel410/restoration/{rio-hardware,rio-firmware}
with full history preserved (git subtree).

Kept here: docs/PROTOCOL.md (this app's interface contract) and the
RioSerialMonitor bench harness (--mash/--e0test, C# on RioJoy.Core).
README + code comments now point at the TeslaRel410 archive.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/RioJoy.Core/Serial/SerialPortTransport.cs

@@ -25,8 +25,8 @@ public sealed class SerialPortTransport : IRioTransport
 
     /// <param name="portName">COM port name, e.g. "COM1".</param>
     /// <param name="baudRate">
-    /// Link rate; default 9600 (stock firmware). The 31250-baud firmware
-    /// variant (rio-firmware/, --baud31250) needs an adapter that can make
+    /// Link rate; default 9600 (stock firmware). The 31250-baud FastRIO
+    /// firmware (TeslaRel410 restoration/rio-firmware) needs an adapter that can make
     /// non-standard rates exactly — FTDI-class USB serial can, classic
     /// 16550 UARTs cannot.
     /// </param>