Fix follow suggestions potentially including silenced or blocked accounts (#29306)

app/models/account_suggestions/friends_of_friends_source.rb

@@ -2,31 +2,15 @@
 
 class AccountSuggestions::FriendsOfFriendsSource < AccountSuggestions::Source
   def get(account, limit: DEFAULT_LIMIT)
-    Account.find_by_sql([<<~SQL.squish, { id: account.id, limit: limit }]).map { |row| [row.id, key] }
-      WITH first_degree AS (
-          SELECT target_account_id
-          FROM follows
-          JOIN accounts AS target_accounts ON follows.target_account_id = target_accounts.id
-          WHERE account_id = :id
-            AND NOT target_accounts.hide_collections
-      )
-      SELECT accounts.id, COUNT(*) AS frequency
-      FROM accounts
-      JOIN follows ON follows.target_account_id = accounts.id
-      JOIN account_stats ON account_stats.account_id = accounts.id
-      LEFT OUTER JOIN follow_recommendation_mutes ON follow_recommendation_mutes.target_account_id = accounts.id AND follow_recommendation_mutes.account_id = :id
-      WHERE follows.account_id IN (SELECT * FROM first_degree)
-        AND NOT EXISTS (SELECT 1 FROM follows f WHERE f.target_account_id = follows.target_account_id AND f.account_id = :id)
-        AND follows.target_account_id <> :id
-        AND accounts.discoverable
-        AND accounts.suspended_at IS NULL
-        AND accounts.silenced_at IS NULL
-        AND accounts.moved_to_account_id IS NULL
-        AND follow_recommendation_mutes.target_account_id IS NULL
-      GROUP BY accounts.id, account_stats.id
-      ORDER BY frequency DESC, account_stats.followers_count ASC
-      LIMIT :limit
-    SQL
+    first_degree = account.following.where.not(hide_collections: true).select(:id).reorder(nil)
+    base_account_scope(account)
+      .joins(:account_stat)
+      .where(id: Follow.where(account_id: first_degree).select(:target_account_id))
+      .group('accounts.id, account_stats.id')
+      .reorder('frequency DESC, followers_count DESC')
+      .limit(limit)
+      .pluck(Arel.sql('accounts.id, COUNT(*) AS frequency'))
+      .map { |id, _frequency| [id, key] }
   end
 
   private