[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/cache/size.go

@@ -19,6 +19,7 @@ package cache
 
 import (
 	"crypto/rsa"
+	"strings"
 	"time"
 	"unsafe"
 
@@ -320,6 +321,20 @@ func sizeofClient() uintptr {
 	}))
 }
 
+func sizeofConversation() uintptr {
+	return uintptr(size.Of(&gtsmodel.Conversation{
+		ID:               exampleID,
+		CreatedAt:        exampleTime,
+		UpdatedAt:        exampleTime,
+		AccountID:        exampleID,
+		OtherAccountIDs:  []string{exampleID, exampleID, exampleID},
+		OtherAccountsKey: strings.Join([]string{exampleID, exampleID, exampleID}, ","),
+		ThreadID:         exampleID,
+		LastStatusID:     exampleID,
+		Read:             util.Ptr(true),
+	}))
+}
+
 func sizeofEmoji() uintptr {
 	return uintptr(size.Of(&gtsmodel.Emoji{
 		ID:                     exampleID,