feat: 完成 DOCX R4 元素级视觉门禁

建立 Chromium、Word 与 WPS 的可编辑内容、段落几何、页眉页脚、封面、媒体和逐页视觉比较链路。

支持封面独立分节、正文页码重启、主题页边距与横向纸张，并将自然分页差异降为诊断项。

修正代码块内边距和折叠表格单元格边框映射，14 套主题生产矩阵与六组布局视觉矩阵通过。

packages/docx-theme-engine/tests/normalizer.test.ts

@@ -40,6 +40,7 @@ const computed: DocxComputedStyle = {
   borderLeft: "0px none rgb(17, 34, 51)",
   width: "640px",
   maxWidth: "none",
+  minWidth: "0px",
   minHeight: "0px",
   height: "24px",
   breakBefore: "auto",
@@ -203,12 +204,40 @@ describe("DOCX 主题令牌归一化", () => {
     expect(findSlot(tokens, "table").style.widthPercent).toBe(100);
   });
 
+  it("按父级内容区归一化右置百分比结构容器", () => {
+    const tokens = resolveDocxThemeTokens({
+      snapshot: createSnapshot({
+        "official-signature": {
+          width: "332.8px",
+          containingBlockWidth: "640px",
+          marginLeft: "307.2px",
+          marginRight: "0px",
+          textAlign: "center"
+        }
+      }),
+      config: {
+        mode: "auto",
+        basePreset: "official",
+        overrides: {},
+        legacyPreset: false
+      }
+    });
+
+    expect(findSlot(tokens, "official-signature").style).toMatchObject({
+      widthPercent: 52,
+      leftIndentPt: 230.4,
+      rightIndentPt: 0,
+      alignment: "center"
+    });
+  });
+
   it("保留封面高度、垂直对齐、轮廓线和隐藏字段语义", () => {
     const tokens = resolveDocxThemeTokens({
       snapshot: createSnapshot({
         "tender-cover": {
           display: "flex",
           flexDirection: "column",
+          alignItems: "center",
           justifyContent: "center",
           minHeight: "220mm",
           borderBottom: "0px none rgb(17, 34, 51)",
@@ -216,7 +245,9 @@ describe("DOCX 主题令牌归一化", () => {
           outlineOffset: "-16px"
         },
         "tender-bidder": {
-          display: "none"
+          display: "none",
+          alignSelf: "flex-end",
+          contentPaddingLeft: "8px"
         }
       }),
       config: {
@@ -231,6 +262,7 @@ describe("DOCX 主题令牌归一化", () => {
     expect(cover.style).toMatchObject({
       minimumHeightPt: 623.622,
       verticalAlignment: "center",
+      childAlignment: "center",
       borders: {
         top: {
           widthPt: 0.75,
@@ -239,7 +271,11 @@ describe("DOCX 主题令牌归一化", () => {
         }
       }
     });
-    expect(findSlot(tokens, "tender-bidder").style.hidden).toBe(true);
+    expect(findSlot(tokens, "tender-bidder").style).toMatchObject({
+      hidden: true,
+      selfAlignment: "right",
+      contentPaddingLeftPt: 6
+    });
     expect(
       tokens.diagnostics.some(
         (entry) =>
@@ -250,6 +286,31 @@ describe("DOCX 主题令牌归一化", () => {
     ).toBe(true);
   });
 
+  it("保留结构槽位的实际宽度以映射 Flex 子项位置", () => {
+    const tokens = resolveDocxThemeTokens({
+      snapshot: createSnapshot({
+        document: {
+          width: "640px",
+          paddingLeft: "8px",
+          paddingRight: "8px"
+        },
+        "project-report-owner": {
+          minWidth: "70%"
+        }
+      }),
+      config: {
+        mode: "auto",
+        basePreset: "formal",
+        overrides: {},
+        legacyPreset: false
+      }
+    });
+
+    expect(
+      findSlot(tokens, "project-report-owner").style.minimumWidthPercent
+    ).toBe(70);
+  });
+
   it("将超出 Word 能力的装饰边收敛并生成诊断", () => {
     const tokens = resolveDocxThemeTokens({
       snapshot: createSnapshot({