refactor(architecture): eliminate internal package and complete cordis single-owner model and repository migration

- Physically purged all legacy internal/ packages, centralized pkg/model/ and pkg/repository/
- Migrated domain models and database repositories into self-contained owner plugins (user, auth, message_gateway, admin, upload, risk_control)
- Decoupled cross-plugin interactions via pure core/contracts and typed EventBus
- Ensured 100% test coverage pass, zero data races (-race clean), and 0 lint issues in make code-check

pkg/persistence/migrator/clickhouse_test.go

@@ -0,0 +1,51 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package migrator
+
+import (
+	"testing"
+
+	"github.com/Rain-kl/Wavelet/pkg/config"
+	"github.com/pressly/goose/v3"
+)
+
+func TestClickHouseMigrationFilesEmbedded(t *testing.T) {
+	entries, err := clickhouseMigrationFS.ReadDir(clickhouseMigrationDir)
+	if err != nil {
+		t.Fatalf("ReadDir(%q) error = %v", clickhouseMigrationDir, err)
+	}
+	if len(entries) == 0 {
+		t.Fatal("expected embedded ClickHouse migrations, got none")
+	}
+
+	found := false
+	for _, entry := range entries {
+		if entry.IsDir() {
+			continue
+		}
+		if entry.Name() == "202606190001_create_user_access_logs.sql" {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Fatal("expected 202606190001_create_user_access_logs.sql in embedded migrations")
+	}
+}
+
+func TestClickHouseGooseDialect(t *testing.T) {
+	if err := goose.SetDialect("clickhouse"); err != nil {
+		t.Fatalf("SetDialect(clickhouse) error = %v", err)
+	}
+}
+
+func TestMigrateClickHouseSkipsWhenDisabled(t *testing.T) {
+	previousEnabled := config.Config.ClickHouse.Enabled
+	config.Config.ClickHouse.Enabled = false
+	t.Cleanup(func() {
+		config.Config.ClickHouse.Enabled = previousEnabled
+	})
+
+	MigrateClickHouse()
+}