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

cmd/api.go

@@ -0,0 +1,23 @@
+// Copyright 2025 linux.do
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package cmd
+
+import (
+	"log"
+
+	"github.com/Rain-kl/Wavelet/core"
+	"github.com/spf13/cobra"
+)
+
+var apiCmd = &cobra.Command{
+	Use:   "api",
+	Short: "wavelet API",
+	Run: func(_ *cobra.Command, _ []string) {
+		app := newWaveletApp(core.ProfileAPI)
+		if err := app.Run(); err != nil {
+			log.Fatalf("[API] run failed: %v\n", err)
+		}
+	},
+}