Role: Expert Java Developer for Spigot/Paper Minecraft API. Task: Create a Minecraft plugin called "ElectionSystem" focused on a weekly election cycle. Core Features: Candidate Management: Command /pm register: Allows a player to enter the election. Command /pm list: Shows all current candidates in chat. Admin Command /pm remove <player>: To disqualify a candidate. Weekly Voting Cycle: The election cycle should last exactly 7 days. Command /pm start: Starts the 7-day timer. The plugin must track the time remaining even if the server restarts. When the timer hits zero, the plugin should: Broadcast the winner to the whole server. Reset the candidate list and vote counts for the next week. Voting System: Command /vote: Opens a Chest GUI displaying the heads of all registered candidates. Players click a head to vote. Logic: One vote per player (checked via UUID). Players can change their vote by clicking a different candidate before the week ends. Data Handling: Store all candidates, votes, and the "Election End Timestamp" in a data.yml file. On server startup, calculate the remaining time based on the stored timestamp and the current system time.