Fix resolving accounts sometimes creating duplicate records for a given AP id (#15364)

* Fix ResolveAccountService accepting mismatching acct: URI

* Set attributes that should be updated regardless of suspension

* Fix key fetching

* Automatically merge remote accounts with duplicate `uri`

* Add tests

* Add "tootctl accounts fix-duplicates"

Finds duplicate accounts sharing a same ActivityPub `id`, re-fetch them and
merge them under the canonical `acct:` URI.

Co-authored-by: Claire <claire.github-309c@sitedethib.com>

app/services/resolve_account_service.rb

@@ -49,7 +49,7 @@ class ResolveAccountService < BaseService
     # Now it is certain, it is definitely a remote account, and it
     # either needs to be created, or updated from fresh data
 
-    process_account!
+    fetch_account!
   rescue Webfinger::Error, Oj::ParseError => e
     Rails.logger.debug "Webfinger query for #{@uri} failed: #{e}"
     nil
@@ -104,16 +104,12 @@ class ResolveAccountService < BaseService
     acct.gsub(/\Aacct:/, '').split('@')
   end
 
-  def process_account!
+  def fetch_account!
     return unless activitypub_ready?
 
     RedisLock.acquire(lock_options) do |lock|
       if lock.acquired?
-        @account = Account.find_remote(@username, @domain)
-
-        next if actor_json.nil?
-
-        @account = ActivityPub::ProcessAccountService.new.call(@username, @domain, actor_json)
+        @account = ActivityPub::FetchRemoteAccountService.new.call(actor_url)
       else
         raise Mastodon::RaceConditionError
       end
@@ -136,13 +132,6 @@ class ResolveAccountService < BaseService
     @actor_url ||= @webfinger.link('self', 'href')
   end
 
-  def actor_json
-    return @actor_json if defined?(@actor_json)
-
-    json        = fetch_resource(actor_url, false)
-    @actor_json = supported_context?(json) && equals_or_includes_any?(json['type'], ActivityPub::FetchRemoteAccountService::SUPPORTED_TYPES) ? json : nil
-  end
-
   def gone_from_origin?
     @gone
   end