Model the problem as a graph where each word is a node, and edges exist between words that differ by exactly one character. The transformation sequence is a path in this graph.

Use BFS starting from `beginWord` to explore all possible one-letter transformations level by level, tracking visited words to avoid cycles and ensure the shortest path is found.

Optimize by precomputing possible one-letter transformations for each word in the `wordList` (e.g., using a wildcard map like `*ot` → `["hot", "dot", "lot"]`) to reduce the branching factor during BFS.