[chore] media and emoji refactoring (#3000)

* start updating media manager interface ready for storing attachments / emoji right away

* store emoji and media as uncached immediately, then (re-)cache on Processing{}.Load()

* remove now unused media workers

* fix tests and issues

* fix another test!

* fix emoji activitypub uri setting behaviour, fix remainder of test compilation issues

* fix more tests

* fix (most of) remaining tests, add debouncing to repeatedly failing media / emojis

* whoops, rebase issue

* remove kim's whacky experiments

* do some reshuffling, ensure emoji uri gets set

* ensure marked as not cached on cleanup

* tweaks to media / emoji processing to handle context canceled better

* ensure newly fetched emojis actually get set in returned slice

* use different varnames to be a bit more obvious

* move emoji refresh rate limiting to dereferencer

* add exported dereferencer functions for remote media, use these for recaching in processor

* add check for nil attachment in updateAttachment()

* remove unused emoji and media fields + columns

* see previous commit

* fix old migrations expecting image_updated_at to exists (from copies of old models)

* remove freshness checking code (seems to be broken...)

* fix error arg causing nil ptr exception

* finish documentating functions with comments, slight tweaks to media / emoji deref error logic

* remove some extra unneeded boolean checking

* finish writing documentation (code comments) for exported media manager methods

* undo changes to migration snapshot gtsmodels, updated failing migration to have its own snapshot

* move doesColumnExist() to util.go in migrations package

internal/processing/admin/admin.go

@@ -20,20 +20,26 @@ package admin
 import (
 	"github.com/superseriousbusiness/gotosocial/internal/cleaner"
 	"github.com/superseriousbusiness/gotosocial/internal/email"
+	"github.com/superseriousbusiness/gotosocial/internal/federation"
 	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
 	"github.com/superseriousbusiness/gotosocial/internal/media"
+	"github.com/superseriousbusiness/gotosocial/internal/processing/common"
 	"github.com/superseriousbusiness/gotosocial/internal/state"
 	"github.com/superseriousbusiness/gotosocial/internal/transport"
 	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
 )
 
 type Processor struct {
-	state               *state.State
-	cleaner             *cleaner.Cleaner
-	converter           *typeutils.Converter
-	mediaManager        *media.Manager
-	transportController transport.Controller
-	emailSender         email.Sender
+	// common processor logic
+	c *common.Processor
+
+	state     *state.State
+	cleaner   *cleaner.Cleaner
+	converter *typeutils.Converter
+	federator *federation.Federator
+	media     *media.Manager
+	transport transport.Controller
+	email     email.Sender
 
 	// admin Actions currently
 	// undergoing processing
@@ -46,21 +52,24 @@ func (p *Processor) Actions() *Actions {
 
 // New returns a new admin processor.
 func New(
+	common *common.Processor,
 	state *state.State,
 	cleaner *cleaner.Cleaner,
+	federator *federation.Federator,
 	converter *typeutils.Converter,
 	mediaManager *media.Manager,
 	transportController transport.Controller,
 	emailSender email.Sender,
 ) Processor {
 	return Processor{
-		state:               state,
-		cleaner:             cleaner,
-		converter:           converter,
-		mediaManager:        mediaManager,
-		transportController: transportController,
-		emailSender:         emailSender,
-
+		c:         common,
+		state:     state,
+		cleaner:   cleaner,
+		converter: converter,
+		federator: federator,
+		media:     mediaManager,
+		transport: transportController,
+		email:     emailSender,
 		actions: &Actions{
 			r:     make(map[string]*gtsmodel.AdminAction),
 			state: state,