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

plugins/infra/storage/objectstore/http.go

@@ -0,0 +1,44 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package objectstore
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"net/url"
+	"time"
+
+	"github.com/Rain-kl/Wavelet/pkg/httppool"
+)
+
+func getHTTPObject(ctx context.Context, baseURL, key string) (*Object, error) {
+	objectURL, err := url.JoinPath(baseURL, key)
+	if err != nil {
+		return nil, fmt.Errorf("build CDN object URL: %w", err)
+	}
+	request, err := http.NewRequestWithContext(ctx, http.MethodGet, objectURL, nil)
+	if err != nil {
+		return nil, fmt.Errorf("create CDN request: %w", err)
+	}
+	const cdnRequestTimeout = 30 * time.Second
+	client := httppool.NewClient(cdnRequestTimeout)
+	response, err := client.Do(request)
+	if err != nil {
+		return nil, fmt.Errorf("get CDN object: %w", err)
+	}
+	if response.StatusCode != http.StatusOK {
+		_ = response.Body.Close()
+		return nil, fmt.Errorf("get CDN object: unexpected status %d", response.StatusCode)
+	}
+	contentType := response.Header.Get("Content-Type")
+	if contentType == "" {
+		contentType = defaultContentType
+	}
+	return &Object{
+		Body:          response.Body,
+		ContentLength: response.ContentLength,
+		ContentType:   contentType,
+	}, nil
+}