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/handler/root_and_404.go

@@ -4,7 +4,6 @@ import (
 	"net/http"
 	"spend-sparrow/internal/core"
 	"spend-sparrow/internal/template"
-	"spend-sparrow/internal/utils"
 
 	"github.com/a-h/templ"
 )
@@ -36,7 +35,7 @@ func (handler IndexImpl) handleRootAnd404() http.HandlerFunc {
 
 		user := core.GetUser(r)
 
-		htmx := utils.IsHtmx(r)
+		htmx := core.IsHtmx(r)
 
 		var comp templ.Component
 
@@ -46,7 +45,7 @@ func (handler IndexImpl) handleRootAnd404() http.HandlerFunc {
 			status = http.StatusNotFound
 		} else {
 			if user != nil {
-				utils.DoRedirect(w, r, "/dashboard")
+				core.DoRedirect(w, r, "/dashboard")
 				return
 			} else {
 				comp = template.Index()