fix(site): use encoding/json

goccy/go-json v0.11.0 and later panic in the indent encoder with a nil pointer dereference, so the dependency update failed its tests. The site generator needs nothing beyond the standard library.

internal/generator/site/generator.go

@@ -9,7 +9,7 @@ import (
 	"strings"
 	"time"
 
-	json "github.com/goccy/go-json"
+	"encoding/json"
 	"github.com/lukaszraczylo/git-velocity/internal/config"
 	"github.com/lukaszraczylo/git-velocity/internal/domain/models"
 )

internal/generator/site/generator_test.go

@@ -6,7 +6,7 @@ import (
 	"testing"
 	"time"
 
-	json "github.com/goccy/go-json"
+	"encoding/json"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"