feat: 媒体库 blob 去重存储与品牌/注册等前端调整

新增：
- blob_store 二进制去重存储 + blob_dedup 测试

其它：
- 后端 settings/auth/media_library/upload/operations 服务与 handler 调整
- 前端品牌（BrandLockup/BrandCropModal/BrandSeoPanel）、注册、媒体库、分析详情页、Header/SiteChrome 等更新

frontend/app/admin/settings/BrandSeoPanel.tsx

@@ -1,6 +1,6 @@
 "use client";
 
-import { Check, ImagePlus, Images, Link2, X } from "lucide-react";
+import { Check, Crop, ImagePlus, Images, Link2, X } from "lucide-react";
 import { useEffect, useRef, useState, type Dispatch, type SetStateAction } from "react";
 import {
   AdminSegmented,
@@ -11,8 +11,6 @@ import BrandCropModal from "@/components/BrandCropModal";
 import BrandLockup from "@/components/BrandLockup";
 import { apiBrandFromMedia, apiUpdateSiteSettings, apiUploadBrand, type PublicSettings } from "@/lib/api";
 import {
-  BRAND_LOGO_FITS,
-  BRAND_LOGO_SIZES,
   brandAccept,
   brandAliasPath,
   brandFileOk,
@@ -313,6 +311,17 @@ export default function BrandSeoPanel({
             >
               <Images size={14} /> 库
             </button>
+            {preview && !/\.(svg|ico)(\?.*)?$/i.test(preview) ? (
+              <button
+                type="button"
+                className="btn btn-line btn-sm"
+                disabled={saving}
+                title="调整画幅、铺法或重新裁剪"
+                onClick={() => openCrop(slot, null, preview)}
+              >
+                <Crop size={14} /> 调整
+              </button>
+            ) : null}
             <button
               type="button"
               className="admin-icon-btn"
@@ -361,7 +370,7 @@ export default function BrandSeoPanel({
               frame
               name={initial.site_name}
               wordmark={initial.site_wordmark}
-              slogan={initial.site_slogan}
+              slogan={initial.brand_slogan_visible ? initial.site_slogan : ""}
               logoLight={previewOf(light)}
               logoDark={previewOf(dark)}
             />
@@ -388,46 +397,9 @@ export default function BrandSeoPanel({
             />
           </div>
           {mark !== "text" ? (
-            <>
-              <div className="admin-brand-studio-field">
-                <span className="admin-brand-studio-kicker">比例</span>
-                <div className="admin-brand-size-row" role="group" aria-label="Logo 比例">
-                  {BRAND_LOGO_SIZES.map((item) => {
-                    const on = logoSize === item.id;
-                    return (
-                      <button
-                        key={item.id}
-                        type="button"
-                        className={`admin-brand-size-chip${on ? " is-on" : ""}`}
-                        onClick={() => {
-                          setLogoSize(item.id);
-                          if (saveError) setSaveError("");
-                        }}
-                      >
-                        <span className="admin-brand-size-chip-label">{item.label}</span>
-                        <span className="admin-brand-size-chip-px">
-                          {item.w}×{item.h}
-                        </span>
-                      </button>
-                    );
-                  })}
-                </div>
-              </div>
-              <div className="admin-brand-studio-field">
-                <span className="admin-brand-studio-kicker">铺法</span>
-                <AdminSegmented
-                  role="group"
-                  size="sm"
-                  ariaLabel="适配方式"
-                  value={logoFit}
-                  onChange={(v) => {
-                    setLogoFit(v);
-                    if (saveError) setSaveError("");
-                  }}
-                  options={BRAND_LOGO_FITS.map((item) => ({ key: item.id, label: item.label }))}
-                />
-              </div>
-            </>
+            <p className="admin-brand-studio-field text-[11.5px] self-center mb-0.5" style={{ color: "var(--ink-3)" }}>
+              画幅与铺法在上传/调整图片的裁剪弹窗中设置
+            </p>
           ) : null}
         </div>
 
@@ -471,6 +443,16 @@ export default function BrandSeoPanel({
           slot={cropSlot}
           seedFile={cropSeedFile}
           seedUrl={cropSeedUrl}
+          logoSize={logoSize}
+          logoFit={logoFit}
+          onSizeChange={(s) => {
+            setLogoSize(s);
+            if (saveError) setSaveError("");
+          }}
+          onFitChange={(f) => {
+            setLogoFit(f);
+            if (saveError) setSaveError("");
+          }}
           onClose={closeCrop}
           onSeedConsumed={() => {
             setCropSeedFile(null);