blaze-host: A/B the RPC routes a real FIFA session actually used

The gate 5-6 live run exercised 14 RPCs the recorded fixtures never covered --
Stats, Clubs, OSDKSettings, SponsoredEvents, Messaging::fetchMessages,
Util::getTelemetryServer, Util::userSettingsLoadAll, UserSessions cmd 0x0008,
and the transport PING -- every one taking the empty-reply fallback.

That Python does the same was an inference from reading its dispatch table.
This sends those exact routes to both backends and diffs the replies:
14/14 byte-identical.

Worth keeping: the fixtures were built from what the responder implements, so
they could never have covered what the client asks for and the responder does
not. Only a live session reveals that surface, and this makes it checkable
afterwards.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

openfut-blaze-host/route-ab.py

@@ -0,0 +1,92 @@
+#!/usr/bin/env python3
+"""Send the routes a real FIFA session used to BOTH backends and diff the replies.
+
+    ./route-ab.py [python-host:port] [rust-host:port]
+
+WHY
+
+The gate 5-6 live session exercised 14 RPCs the recorded fixtures never covered
+-- Stats, Clubs, OSDKSettings, SponsoredEvents, Messaging::fetchMessages,
+Util::getTelemetryServer, the transport PING -- and every one took the
+empty-reply fallback. That Python does the same was an INFERENCE from reading
+its dispatch table. This turns it into evidence, using the routes FIFA actually
+sent.
+
+None of these RPCs read their request body (they are unhandled on both sides),
+so sending them with an empty payload exercises the same path the client did.
+
+Read-only: opens a client connection to each backend and sends requests. All
+routes here are unimplemented on both sides, so nothing mutates.
+"""
+import socket, struct, sys
+
+# (component, command, msg_type) observed in the live FIFA session.
+MESSAGE, PING = 0, 4
+ROUTES = [
+    (0x0009, 0x0005, MESSAGE, "Util::getTelemetryServer"),
+    (0x0009, 0x000C, MESSAGE, "Util::userSettingsLoadAll"),
+    (0x0009, 0x001C, MESSAGE, "Util::setClientState"),
+    (0x7802, 0x0008, MESSAGE, "UserSessions::cmd:0x0008"),
+    (0x000F, 0x0002, MESSAGE, "Messaging::fetchMessages"),
+    (0x000B, 0x0640, MESSAGE, "Clubs::cmd:0x0640"),
+    (0x000B, 0x0A28, MESSAGE, "Clubs::cmd:0x0a28"),
+    (0x08C9, 0x0001, MESSAGE, "OSDKSettings::cmd:0x0001"),
+    (0x08C9, 0x0002, MESSAGE, "OSDKSettings::cmd:0x0002"),
+    (0x0007, 0x0003, MESSAGE, "Stats::cmd:0x0003"),
+    (0x0007, 0x000F, MESSAGE, "Stats::cmd:0x000f"),
+    (0x0007, 0x0014, MESSAGE, "Stats::cmd:0x0014"),
+    (0x081C, 0x0003, MESSAGE, "SponsoredEvents::cmd:0x0003"),
+    (0x0000, 0x0000, PING,    "transport PING"),
+]
+
+def frame(comp, cmd, num, mtype, payload=b""):
+    h = bytearray(16)
+    struct.pack_into(">I", h, 0, len(payload))
+    struct.pack_into(">H", h, 4, 0)
+    struct.pack_into(">H", h, 6, comp)
+    struct.pack_into(">H", h, 8, cmd)
+    h[10], h[11], h[12] = (num >> 16) & 0xFF, (num >> 8) & 0xFF, num & 0xFF
+    h[13] = (mtype & 7) << 5
+    return bytes(h) + payload
+
+def ask(host, port, routes):
+    s = socket.create_connection((host, port), timeout=10)
+    s.settimeout(10)
+    out, buf = [], b""
+    for i, (comp, cmd, mtype, name) in enumerate(routes):
+        s.sendall(frame(comp, cmd, i + 1, mtype))
+        while len(buf) < 16:
+            d = s.recv(65536)
+            if not d:
+                out.append((name, "NO REPLY")); s.close(); return out
+            buf += d
+        total = 16 + struct.unpack_from(">H", buf, 4)[0] + struct.unpack_from(">I", buf, 0)[0]
+        while len(buf) < total:
+            buf += s.recv(65536)
+        out.append((name, buf[:total].hex()))
+        buf = buf[total:]
+    s.close()
+    return out
+
+def endpoint(arg, default_port):
+    if ":" in arg:
+        h, p = arg.rsplit(":", 1)
+        return h, int(p)
+    return arg, default_port
+
+args = sys.argv[1:]
+PY_HOST, PY_PORT = endpoint(args[0], 42130) if len(args) > 0 else ("127.0.0.1", 42130)
+RS_HOST, RS_PORT = endpoint(args[1], 42230) if len(args) > 1 else ("127.0.0.1", 42230)
+
+print("python %s:%d   rust %s:%d" % (PY_HOST, PY_PORT, RS_HOST, RS_PORT))
+py = ask(PY_HOST, PY_PORT, ROUTES)
+rs = ask(RS_HOST, RS_PORT, ROUTES)
+
+bad = 0
+for (n1, a), (n2, b) in zip(py, rs):
+    same = (a == b)
+    if not same:
+        bad += 1
+    print("  %-32s %s" % (n1, "identical" if same else "DIFFERS\n      py=%s\n      rs=%s" % (a, b)))
+print("\n%d/%d identical" % (len(ROUTES) - bad, len(ROUTES)))
+sys.exit(1 if bad else 0)