Highlight Overlapping Phrases in a Sentence
Company: Harvey
Role: Software Engineer
Category: Software Engineering Fundamentals
Difficulty: hard
Interview Round: Technical Screen
Overview: Given a sentence such as `The quick brown fox jumps over the lazy dog.` and phrases such as `quick brown` and `brown fox jumps`, design a function that returns the sentence with every character covered by any exact phrase match highlighted. Make the API or object boundaries explicit, then cover invariants, edge cases, testing strategy, and operational trade-offs.