feat: add computers as second objective type

- New: Computer, ComputerManager, ComputerRepair, ComputerHologram, ComputerDataManager
- Config: total-count=2, required-count=2, repair-seconds=90 in game.yml
- Win condition: all generators AND all computers required
- No regression, no ComputerKick, no compass on skill-check fail
- /dbdsetup set computer, /dbdadmin list computer
- Hologram progress display, persistence to data/computers.yml
- LECTERN block right-click cancelled

src/main/java/dev/loki/objective/Computer.java

@@ -0,0 +1,146 @@
+package dev.loki.objective;
+
+import dev.loki.data.ComputerDataManager;
+import org.bukkit.Location;
+import org.bukkit.block.Block;
+import org.bukkit.entity.Player;
+
+import java.util.UUID;
+
+public class Computer {
+    private final int id;
+    private final Location location;
+    private final double zoneRadius;
+    private double progress;
+    private boolean isCompleted;
+    private boolean isBlocked;
+    private UUID currentRepairer;
+    private int regressionTicks;
+    private boolean wasKicked;
+
+    public Computer(int id, Location location) {
+        this(id, location, ComputerDataManager.getZoneRadius());
+    }
+
+    public Computer(int id, Location location, double zoneRadius) {
+        this.id = id;
+        this.location = location;
+        this.zoneRadius = zoneRadius;
+        this.progress = 0.0;
+        this.isCompleted = false;
+        this.isBlocked = false;
+        this.currentRepairer = null;
+        this.regressionTicks = 0;
+        this.wasKicked = false;
+    }
+
+    public int getId() {
+        return id;
+    }
+
+    public Location getLocation() {
+        return location;
+    }
+
+    public double getZoneRadius() {
+        return zoneRadius;
+    }
+
+    public boolean isPlayerInZone(Player player) {
+        if (!player.getWorld().equals(location.getWorld())) return false;
+        return player.getLocation().distance(location) <= zoneRadius;
+    }
+
+    public boolean isLocationInZone(Location loc) {
+        if (!loc.getWorld().equals(location.getWorld())) return false;
+        return loc.distance(location) <= zoneRadius;
+    }
+
+    public double getProgress() {
+        return progress;
+    }
+
+    public void setProgress(double progress) {
+        this.progress = Math.max(0, Math.min(100, progress));
+        if (this.progress >= 100) {
+            this.progress = 100;
+            this.isCompleted = true;
+        }
+    }
+
+    public void addProgress(double amount) {
+        setProgress(progress + amount);
+    }
+
+    public void removeProgress(double amount) {
+        setProgress(progress - amount);
+    }
+
+    public boolean isCompleted() {
+        return isCompleted;
+    }
+
+    public boolean isBlocked() {
+        return isBlocked;
+    }
+
+    public void setBlocked(boolean blocked) {
+        this.isBlocked = blocked;
+    }
+
+    public UUID getCurrentRepairer() {
+        return currentRepairer;
+    }
+
+    public void setCurrentRepairer(UUID repairer) {
+        this.currentRepairer = repairer;
+    }
+
+    public boolean isBeingRepaired() {
+        return currentRepairer != null;
+    }
+
+    public int getRegressionTicks() {
+        return regressionTicks;
+    }
+
+    public void setRegressionTicks(int ticks) {
+        this.regressionTicks = ticks;
+    }
+
+    public void decrementRegression() {
+        if (regressionTicks > 0) {
+            regressionTicks--;
+        }
+    }
+
+    public boolean isUnderRegression() {
+        return regressionTicks > 0 && !isCompleted && !isBeingRepaired();
+    }
+
+    public void setUnderRegression(boolean kicked, int durationTicks) {
+        this.wasKicked = kicked;
+        this.regressionTicks = durationTicks;
+    }
+
+    public boolean wasKicked() {
+        return wasKicked;
+    }
+
+    public void setKicked(boolean kicked) {
+        this.wasKicked = kicked;
+    }
+
+    public boolean canBeRepaired() {
+        return !isCompleted && !isBlocked && !isUnderRegression();
+    }
+
+    @Deprecated
+    public Block getBlock() {
+        return location.getBlock();
+    }
+
+    public double getDistance(Location loc) {
+        return location.distance(loc);
+    }
+}