Replace cheat-detection teleport with server reconciliation

The old PUNKBUSTER check compared client-reported position to server
position and snapped the player back when latency made them diverge,
which felt like getting teleported under any real network conditions.

Replaces that with proper client-side prediction + reconciliation:
client tags each input with a sequence number and keeps an input
buffer; server tracks the last processed sequence and reports its
authoritative position via a per-user inputAck alongside each
worldUpdate. The client only corrects when the actual disagreement
exceeds what the unacked input time can explain — so steady-state
movement runs purely on local physics, and only genuine unexpected
events (collisions, being hit) trigger a smooth blend toward the
server state.

Includes adaptive threshold scaling so high-latency sessions don't
false-positive corrections during normal running.

app/Game/Client/InputBuffer.js

@@ -0,0 +1,37 @@
+define([
+],
+
+function () {
+
+    "use strict";
+
+    var MAX_BUFFER_SIZE = 300;
+
+    function InputBuffer() {
+        this._buffer = [];
+    }
+
+    InputBuffer.prototype.add = function(entry) {
+        this._buffer.push(entry);
+        if (this._buffer.length > MAX_BUFFER_SIZE) {
+            this._buffer.shift();
+        }
+    };
+
+    InputBuffer.prototype.acknowledgeUpTo = function(seq) {
+        while (this._buffer.length > 0 && this._buffer[0].seq <= seq) {
+            this._buffer.shift();
+        }
+    };
+
+    InputBuffer.prototype.getUnacknowledged = function() {
+        return this._buffer;
+    };
+
+    InputBuffer.prototype.clear = function() {
+        this._buffer = [];
+    };
+
+    return InputBuffer;
+
+});