constructor(tokenId, nodeId, pos, length, score) {
        this.tokenId = tokenId;
        this.nodeId = nodeId;
        this.pos = pos;
        this.length = length;
        this.score = score;
        this.prev = null;
        this.backtraceScore = 0.0;
    }
Represents a node in a token lattice for a given sentence.
@param {number} tokenId The ID of the token associated with this node.
@param {number} nodeId The ID of this node.
@param {number} pos The starting position of the token in the sentence.
@param {number} length The length of the token.
@param {number} score The score associated with the token.