feat: 前端HESUPIPE品牌化+管道文案+GDPR提示

- 品牌色橙#f08a31→HESUPIPE蓝#066fc0(取自官网主题CSS a:hover/导航主色),7槽位色板三处同步:theme.js/widget.js内联副本/style.css :root
- chat.html/widget.js/js/chat.js:标题HESUPIPE Support、管道场景描述、欢迎语、热门话题Get Quotation/Pipe Specifications/Delivery & Shipping、WhatsApp+8615937108317、邮箱hesu@hesuu.com
- 邀请卡文案管道化(pipe specs, MOQ, delivery timing)+GDPR小字;聊天面板footer GDPR行(复用.chat-footer)
- admin.html VOLT→HESUPIPE;头像PIL重绘为品牌蓝底白H(512/128px)
- widget-test.html色值同步+断言基准更新(浏览器断言9/9 Δ=0);.gitignore排除.playwright-mcp/

Co-Authored-By: Claude Code <noreply@anthropic.com>

static/js/theme.js

@@ -4,16 +4,16 @@
 (function (global) {
     "use strict";
 
-    var DEFAULT_COLOR = "#f08a31";
+    var DEFAULT_COLOR = "#066fc0";
 
     var DEFAULT_PALETTE = {
-        primary: "#f08a31",
-        primaryRgb: "240,138,49",
-        gradientEnd: "#f08e2c",
-        deepText: "#8a4c1d",
-        captionText: "#c16d2d",
-        softBg: "#fef8f4",
-        borderSoft: "#f0d3bd"
+        primary: "#066fc0",
+        primaryRgb: "6,111,192",
+        gradientEnd: "#0666bb",
+        deepText: "#14517a",
+        captionText: "#2174ab",
+        softBg: "#f3f9fe",
+        borderSoft: "#bbdcf2"
     };
 
     function clampNum(v, lo, hi) {