feat: add typescript declaration files

Types are automatically generated from the existsing
JSDoc comments in the js source code. Use `types:build`
script from `package.json` to produce d.ts files.

types/lib/varint.d.ts

@@ -0,0 +1,49 @@
+/**
+ * Encodes an integer into a VarInt buffer.
+ * VarInts are never longer than 5 bytes for the Minecraft protocol.
+ * @param {number} value The integer to encode
+ * @returns {Buffer} The encoded VarInt as a buffer
+ * @throws {VarIntError} if the value is too large to be encoded
+ */
+export function encodeVarInt(value: number): Buffer;
+/**
+ * Encodes a string into a UTF-8 buffer.
+ * @param {string} value The string to encode
+ * @returns {Buffer}
+ */
+export function encodeString(value: string): Buffer;
+/**
+ * Encodes an unsigned short (16-bit big-endian) into a 2-byte buffer.
+ * @param {number} value The number to encode
+ * @returns {Buffer}
+ */
+export function encodeUShort(value: number): Buffer;
+/**
+ * Creates a Minecraft-style packet by concatenating chunks and prefixing the total length as a VarInt.
+ * @param {Buffer[]} chunks An array of buffers to include in the packet payload
+ * @returns {Buffer} The complete packet with its length prefix
+ */
+export function concatPackets(chunks: Buffer[]): Buffer;
+/**
+ * Decodes a VarInt from a buffer.
+ * Returns the decoded value and the number of bytes it consumed.
+ * @param {Buffer} buffer The buffer to read from
+ * @param {number} [offset=0] The starting offset in the buffer
+ * @returns {{ value: number, bytesRead: number }}
+ * @throws {VarIntError} if the buffer is too short or the VarInt is malformed
+ */
+export function decodeVarInt(buffer: Buffer, offset?: number): {
+    value: number;
+    bytesRead: number;
+};
+export const ERR_VARINT_BUFFER_UNDERFLOW: "VARINT_BUFFER_UNDERFLOW";
+export const ERR_VARINT_MALFORMED: "VARINT_MALFORMED";
+export const ERR_VARINT_ENCODE_TOO_LARGE: "VARINT_ENCODE_TOO_LARGE";
+export class VarIntError extends Error {
+    /**
+     * @param {string} message The error message.
+     * @param {string} code The error code.
+     */
+    constructor(message: string, code: string);
+    code: string;
+}