FEATURE: allow TL3 promotions for overturned penalties

Restore tl3 reachability by calculating penalty counts vs unsuspend/unsilence.

Only count unsuspend or unsilences that have been made by a user other than
the Discourse system user.

app/models/trust_level3_requirements.rb

@@ -104,18 +104,33 @@ class TrustLevel3Requirements
   def penalty_counts
     args = {
       user_id: @user.id,
+      system_user_id: Discourse.system_user.id,
       silence_user: UserHistory.actions[:silence_user],
+      unsilence_user: UserHistory.actions[:unsilence_user],
       suspend_user: UserHistory.actions[:suspend_user],
+      unsuspend_user: UserHistory.actions[:unsuspend_user],
       since: FORGIVENESS_PERIOD.ago
     }
 
     sql = <<~SQL
       SELECT
-        SUM(CASE WHEN action = :silence_user THEN 1 ELSE 0 END) AS silence_count,
-        SUM(CASE WHEN action = :suspend_user THEN 1 ELSE 0 END) AS suspend_count
+      SUM(
+          CASE
+            WHEN action = :silence_user THEN 1
+            WHEN action = :unsilence_user AND acting_user_id != :system_user_id THEN -1
+            ELSE 0
+          END
+        ) AS silence_count,
+        SUM(
+          CASE
+            WHEN action = :suspend_user THEN 1
+            WHEN action = :unsuspend_user AND acting_user_id != :system_user_id THEN -1
+            ELSE 0
+          END
+        ) AS suspend_count
       FROM user_histories AS uh
       WHERE uh.target_user_id = :user_id
-        AND uh.action IN (:silence_user, :suspend_user)
+        AND uh.action IN (:silence_user, :suspend_user, :unsilence_user, :unsuspend_user)
         AND uh.created_at > :since
     SQL