feat: extract into remaining packages

There has been a cyclic dependency.
transaction
	-> treasure_chest
	-> transaction_recurring
	-> transaction

This has been temporarily solved by moving the GenerateTransactions
function into the transaction package. In the future, this function has
to be rewritten to use a proper Service insteas of direct DB access or
replaced with a different system entirely.

internal/authentication/service.go

@@ -9,7 +9,6 @@ import (
 	"spend-sparrow/internal/auth_types"
 	"spend-sparrow/internal/core"
 	mailTemplate "spend-sparrow/internal/template/mail"
-	"spend-sparrow/internal/types"
 	"strings"
 	"time"
 
@@ -54,10 +53,10 @@ type ServiceImpl struct {
 	random         core.Random
 	clock          core.Clock
 	mail           core.Mail
-	serverSettings *types.Settings
+	serverSettings *core.Settings
 }
 
-func NewService(db Db, random core.Random, clock core.Clock, mail core.Mail, serverSettings *types.Settings) *ServiceImpl {
+func NewService(db Db, random core.Random, clock core.Clock, mail core.Mail, serverSettings *core.Settings) *ServiceImpl {
 	return &ServiceImpl{
 		db:             db,
 		random:         random,