feat(protocol): negotiate display and native input

tools/native_conformance.swift

@@ -27,8 +27,9 @@ func evaluate(_ kind: String, _ input: String) -> String {
         guard let sequence = Int(values["sequence"] ?? ""), sequence > 0, values["correlation_id"] != nil else { return "invalid:required" }
         return "valid"
     case "tunnel":
-        if ["1", "0", "-1"].contains(values["offered"] ?? "") && values["feature"] == "control.v1" { return "valid" }
-        return values["feature"] == "control.v1" ? "invalid:unsupported_version" : "invalid:unsupported_feature"
+        let registered = ["control.v1", "display.request.v1", "input.absolute.v1", "input.scroll.v1"].contains(values["feature"] ?? "")
+        if ["1", "0", "-1"].contains(values["offered"] ?? "") && registered { return "valid" }
+        return registered ? "invalid:unsupported_version" : "invalid:unsupported_feature"
     case "datagram": return classifyDatagram(values["hex"] ?? "")
     case "gateway_input": return classifyGatewayInput(values["hex"] ?? "")
     case "gateway_feedback": return classifyGatewayFeedback(values["hex"] ?? "")
@@ -82,6 +83,14 @@ func classifyGatewayInput(_ encoded: String) -> String {
         guard body[0] <= 15 else { return "invalid:field" }
         guard body[1] != 0 || body[2] != 0 || body.dropFirst(3).allSatisfy({ $0 == 0 }) else { return "invalid:field" }
         return "valid"
+    case 6:
+        guard body.count == 8 else { return "invalid:length" }
+        let x = Int(body[0]) * 256 + Int(body[1])
+        let y = Int(body[2]) * 256 + Int(body[3])
+        let width = Int(body[4]) * 256 + Int(body[5])
+        let height = Int(body[6]) * 256 + Int(body[7])
+        return width > 0 && height > 0 && x < width && y < height ? "valid" : "invalid:field"
+    case 7: return body.count == 4 ? "valid" : "invalid:length"
     default: return "invalid:kind"
     }
 }