[feature] Conversations API (#3013)

* Implement conversations API

* Sort and page conversations by last status ID

* Appease linter

* Fix deleting conversations and statuses

* Refactor to make migrations automatic

* Lint

* Update tests post-merge

* Fixes from live-fire testing

* Linter caught a format problem

* Refactor tests, fix cache

* Negative test for non-DMs

* Run conversations advanced migration on testrig startup as well as regular server startup

* Document (lack of) side effects of API method for deleting a conversation

* Make not-found check less nested for readability

* Rename PutConversation to UpsertConversation

* Use util.Ptr instead of IIFE

* Reduce cache used by conversations

* Remove unnecessary TableExpr/ColumnExpr

* Use struct tags for both unique constraints on Conversation

* Make it clear how paging with GetDirectStatusIDsBatch should be used

* Let conversation paging skip conversations it can't render

* Use Bun NewDropTable

* Convert delete raw query to Bun

* Convert update raw query to Bun

* Convert latestConversationStatusesTempTable raw query partially to Bun

* Convert conversationStatusesTempTable raw query partially to Bun

* Rename field used to store result of MaxDirectStatusID

* Move advanced migrations to their own tiny processor

* Catch up util function name with main

* Remove json.… wrappers

* Remove redundant check

* Combine error checks

* Replace map with slice of structs

* Address processor/type converter comments

- Add context info for errors
- Extract some common processor code into shared methods
- Move conversation eligibility check ahead of populating conversation

* Add error context when dropping temp tables

internal/processing/workers/surface.go

@@ -20,6 +20,7 @@ package workers
 import (
 	"github.com/superseriousbusiness/gotosocial/internal/email"
 	"github.com/superseriousbusiness/gotosocial/internal/filter/visibility"
+	"github.com/superseriousbusiness/gotosocial/internal/processing/conversations"
 	"github.com/superseriousbusiness/gotosocial/internal/processing/stream"
 	"github.com/superseriousbusiness/gotosocial/internal/state"
 	"github.com/superseriousbusiness/gotosocial/internal/typeutils"
@@ -32,9 +33,10 @@ import (
 //   - sending a notification to a user
 //   - sending an email
 type Surface struct {
-	State       *state.State
-	Converter   *typeutils.Converter
-	Stream      *stream.Processor
-	Filter      *visibility.Filter
-	EmailSender email.Sender
+	State         *state.State
+	Converter     *typeutils.Converter
+	Stream        *stream.Processor
+	Filter        *visibility.Filter
+	EmailSender   email.Sender
+	Conversations *conversations.Processor
 }