[feature] List replies policy, refactor async workers (#2087)

* Add/update some DB functions.

* move async workers into subprocessor

* rename FromFederator -> FromFediAPI

* update home timeline check to include check for current status first before moving to parent status

* change streamMap to pointer to mollify linter

* update followtoas func signature

* fix merge

* remove errant debug log

* don't use separate errs.Combine() check to wrap errs

* wrap parts of workers functionality in sub-structs

* populate report using new db funcs

* embed federator (tiny bit tidier)

* flesh out error msg, add continue(!)

* fix other error messages to be more specific

* better, nicer

* give parseURI util function a bit more util

* missing headers

* use pointers for subprocessors

internal/processing/workers/surface.go

@@ -0,0 +1,40 @@
+// GoToSocial
+// Copyright (C) GoToSocial Authors admin@gotosocial.org
+// SPDX-License-Identifier: AGPL-3.0-or-later
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Affero General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU Affero General Public License for more details.
+//
+// You should have received a copy of the GNU Affero General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package workers
+
+import (
+	"github.com/superseriousbusiness/gotosocial/internal/email"
+	"github.com/superseriousbusiness/gotosocial/internal/processing/stream"
+	"github.com/superseriousbusiness/gotosocial/internal/state"
+	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
+	"github.com/superseriousbusiness/gotosocial/internal/visibility"
+)
+
+// surface wraps functions for 'surfacing' the result
+// of processing a message, eg:
+//   - timelining a status
+//   - removing a status from timelines
+//   - sending a notification to a user
+//   - sending an email
+type surface struct {
+	state       *state.State
+	tc          typeutils.TypeConverter
+	stream      *stream.Processor
+	filter      *visibility.Filter
+	emailSender email.Sender
+}