STALKER: Composed Quasi-Identifiers and LLM-Amplified Behavioral Leakage in Anonymized Marketplace Data. - Anastasiya Dmytryk; Sami El Yaagoubi; Lucas Batista; Philipp Kouterguine; Samuel Gerken; Abdulaziz Alhamadani; Karim Elish (IWSPA@CODASPY, 2026)