Fit this lamp: 4 alarms, full data model, knock snooze, server use

Decode DP127 as 48 bytes (4 alarms), plus DP128, DP107 and DP126, from Tuya's
data model. Add day switches, alarm and sunset controls, a knock sensor on PA18,
display schedule, bedtime fade, radio timer and grouped web UI. Pin LibreTiny
v1.14.0 for the OTA restart fix. Ship the patched UART as an external component
so a server needs only a short YAML.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

components/uart/packet_transport/uart_transport.h

@@ -0,0 +1,38 @@
+#pragma once
+
+#include "esphome/core/component.h"
+#include "esphome/components/packet_transport/packet_transport.h"
+#include <vector>
+#include "../uart.h"
+
+namespace esphome::uart {
+
+/**
+ * A transport protocol for sending and receiving packets over a UART connection.
+ * The protocol is based on Asynchronous HDLC framing. (https://en.wikipedia.org/wiki/High-Level_Data_Link_Control)
+ * There are two special bytes: FLAG_BYTE and CONTROL_BYTE.
+ * A 16-bit CRC is appended to the packet, then
+ * the protocol wraps the resulting data between FLAG_BYTEs.
+ * Any occurrence of FLAG_BYTE or CONTROL_BYTE in the data is escaped by emitting CONTROL_BYTE followed by the byte
+ * XORed with 0x20.
+ */
+static const uint16_t MAX_PACKET_SIZE = 508;
+static const uint8_t FLAG_BYTE = 0x7E;
+static const uint8_t CONTROL_BYTE = 0x7D;
+
+class UARTTransport final : public packet_transport::PacketTransport, public UARTDevice {
+ public:
+  void loop() override;
+  float get_setup_priority() const override { return setup_priority::PROCESSOR; }
+
+ protected:
+  void write_byte_(uint8_t byte) const;
+  void send_packet(const std::vector<uint8_t> &buf) const override;
+  bool should_send() override { return true; };
+  size_t get_max_packet_size() override { return MAX_PACKET_SIZE; }
+  std::vector<uint8_t> receive_buffer_{};
+  bool rx_started_{};
+  bool rx_control_{};
+};
+
+}  // namespace esphome::uart