Add workaround for plugins adding/removing/modifying permission attachments via reflection (#1024)

who knows why they're doing it, it's not even beneficial for performance...

sponge/sponge-service-api6/src/main/java/me/lucko/luckperms/sponge/service/proxy/api6/SubjectProxy.java

@@ -173,6 +173,11 @@ public final class SubjectProxy implements Subject, ProxiedSubject {
         return CompatibilityUtil.convertContexts(getContextsCache().getContextSet());
     }
 
+    @Override
+    public ImmutableContextSet getActiveContextSet() {
+        return getContextsCache().getContextSet();
+    }
+
     @Override
     public boolean equals(Object o) {
         return o == this || o instanceof SubjectProxy && this.ref.equals(((SubjectProxy) o).ref);

sponge/sponge-service-api7/src/main/java/me/lucko/luckperms/sponge/service/proxy/api7/SubjectProxy.java

@@ -174,6 +174,11 @@ public final class SubjectProxy implements Subject, ProxiedSubject {
         return CompatibilityUtil.convertContexts(getContextsCache().getContextSet());
     }
 
+    @Override
+    public ImmutableContextSet getActiveContextSet() {
+        return getContextsCache().getContextSet();
+    }
+
     @Override
     public boolean equals(Object o) {
         return o == this || o instanceof SubjectProxy && this.ref.equals(((SubjectProxy) o).ref);

sponge/sponge-service/src/main/java/me/lucko/luckperms/sponge/service/model/ProxiedSubject.java

@@ -25,6 +25,8 @@
 
 package me.lucko.luckperms.sponge.service.model;
 
+import me.lucko.luckperms.api.context.ImmutableContextSet;
+
 import org.spongepowered.api.service.permission.Subject;
 
 import javax.annotation.Nonnull;
@@ -37,4 +39,6 @@ public interface ProxiedSubject {
     @Nonnull
     LPSubjectReference asSubjectReference();
 
+    ImmutableContextSet getActiveContextSet();
+
 }