feat: 本地嵌入 Font Awesome 字体，修复 Brands 被映射成 Arial

本项目不实现通用字体嵌入（由云端完成），但 Font Awesome 的 icon
字形必须随 PPTX 走，否则在没装 FA 的机器上图标会变方块。

- 新增预构建的 PowerPoint 兼容 EOT（FA5/FA6: solid/regular/brands
  + v4compatibility），用 ../html2pptx 的 sanitize+sfnttool 一次性
  生成，运行时不再做 ttf→eot 转换
- 新增 src/utils/fa-font-embedder.ts：扫描 PPTX XML 里的 typeface，
  只嵌入 FA 字体，更新 [Content_Types].xml / presentation.xml / .rels
- 在 convertHtmlToPptx 生成 PPTX 后调用嵌入（仅本地模式）
- 修复 Brands 既有 bug：normalizeFontAwesomeFreeFamily 跳过 brands，
  导致 --platform 启用时 fab 图标被错误映射成 Arial；新增
  normalizeFontAwesomeFamily 统一处理 Solid/Regular/Brands/v4

Author: zhaoxiongfei

assets/fonts/font-awesome/5/fa-brands-400.eot

@@ -1,6 +1,6 @@
 {
   "name": "@deckflow/deckhtml",
-  "version": "0.3.0",
+  "version": "0.3.1",
   "description": "Convert HTML to PPTX or PNG presentations",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
@@ -14,6 +14,7 @@
   "scripts": {
     "build": "tsc",
     "build:font-index": "npx tsx src/bin/build-embed-font-index.ts",
+    "build:fa-eot": "node scripts/build-fa-eot.mjs",
     "dev": "tsc --watch",
     "clean": "rm -rf dist/",
     "link:dev": "npm run build && npm link",

assets/fonts/font-awesome/5/fa-regular-400.eot

@@ -0,0 +1,56 @@
+// One-time script: generate PowerPoint-compatible EOTs from Font Awesome TTFs.
+// Uses html2pptx's sanitize + sfnttool pipeline. Output is committed to deckhtml.
+// Run from deckhtml root: node scripts/build-fa-eot.mjs
+import { execFileSync } from 'child_process';
+import { existsSync, mkdirSync, readFileSync, rmSync, writeFileSync } from 'fs';
+import os from 'os';
+import path from 'path';
+import { fileURLToPath } from 'url';
+
+const __dirname = path.dirname(fileURLToPath(import.meta.url));
+const DECKHTML_ROOT = path.resolve(__dirname, '..');
+const HTML2PPTX_ROOT = path.resolve(DECKHTML_ROOT, '../html2pptx');
+const FONTS_ROOT = path.resolve(DECKHTML_ROOT, '../../fonts/fonts/font-awesome');
+const OUT_ROOT = path.resolve(DECKHTML_ROOT, 'assets/fonts/font-awesome');
+
+const SANITIZE_SCRIPT = path.join(HTML2PPTX_ROOT, 'tools/sanitize-ttf-for-eot.py');
+const SFNTTOOL_JAR = path.join(HTML2PPTX_ROOT, 'tools/sfnttool.jar');
+
+const TARGETS = [
+  { ver: '6', src: 'fa-solid-900.ttf', out: 'fa-solid-900.eot' },
+  { ver: '6', src: 'fa-regular-400.ttf', out: 'fa-regular-400.eot' },
+  { ver: '6', src: 'fa-brands-400.ttf', out: 'fa-brands-400.eot' },
+  { ver: '6', src: 'fa-v4compatibility.ttf', out: 'fa-v4compatibility.eot' },
+  { ver: '5', src: 'fa-solid-900.ttf', out: 'fa-solid-900.eot' },
+  { ver: '5', src: 'fa-regular-400.ttf', out: 'fa-regular-400.eot' },
+  { ver: '5', src: 'fa-brands-400.ttf', out: 'fa-brands-400.eot' },
+];
+
+function run(cmd, args, opts = {}) {
+  execFileSync(cmd, args, { stdio: 'inherit', timeout: 300_000, ...opts });
+}
+
+function buildOne({ ver, src, out }) {
+  const ttfIn = path.join(FONTS_ROOT, ver, src);
+  if (!existsSync(ttfIn)) {
+    console.warn(`skip (missing source TTF): ${ttfIn}`);
+    return;
+  }
+  const tmp = fs.mkdtempSync(path.join(os.tmpdir(), 'fa-eot-'));
+  try {
+    const sanitizedTtf = path.join(tmp, 'sanitized.ttf');
+    const eotOut = path.join(tmp, out);
+    run('python3', [SANITIZE_SCRIPT, ttfIn, sanitizedTtf]);
+    run('java', ['-jar', SFNTTOOL_JAR, '-e', '-x', '-h', sanitizedTtf, eotOut]);
+    const outDir = path.join(OUT_ROOT, ver);
+    mkdirSync(outDir, { recursive: true });
+    writeFileSync(path.join(outDir, out), readFileSync(eotOut));
+    console.log(`✓ ${ver}/${out} (${readFileSync(eotOut).length} bytes)`);
+  } finally {
+    rmSync(tmp, { recursive: true, force: true });
+  }
+}
+
+import fs from 'fs';
+for (const t of TARGETS) buildOne(t);
+console.log('Done.');

assets/fonts/font-awesome/5/fa-solid-900.eot

@@ -21,6 +21,7 @@ import {
   isBold,
   isItalic,
   normalizeFontAwesomeFreeFamily,
+  normalizeFontAwesomeFamily,
   parseScriptFontFaces,
 } from './utils/style';
 import {
@@ -29,6 +30,7 @@ import {
 } from './utils/textScript';
 import { buildPlatformFontContext, PlatformFontContext } from './utils/platformFontMap';
 import { runQuietly } from './utils/quiet';
+import { embedFontAwesomeFonts } from './utils/fa-font-embedder';
 import { buildElementStats, buildFontStats, buildSimplifiedStats } from './conversion-report';
 
 /**
@@ -121,6 +123,11 @@ function collectFontsFromElements(
       registerFont(faFreeFace, styles, false);
       return;
     }
+    const faFace = normalizeFontAwesomeFamily(styles.fontFamily, styles.fontWeight?.toString());
+    if (faFace) {
+      registerFont(faFace, styles, false);
+      return;
+    }
 
     const scripts = new Set(
       texts.flatMap((text) => collectTextScripts(text, containerText))
@@ -483,10 +490,15 @@ export async function convertHtmlToPptx(
   const data = await generator.generate(mergedSlidesMap);
   const slideCount = generator.getSlideCount();
 
+  // Font Awesome is the only font family embedded locally — its icon glyphs must
+  // travel with the PPTX or icons render as empty boxes on machines without FA.
+  // All other font embedding is handled by the cloud pipeline.
+  const dataWithFaFonts = await embedFontAwesomeFonts(data);
+
   reportUsedFonts(usedFontsDeduped, fontStats);
 
   return {
-    data,
+    data: dataWithFaFonts,
     usedFonts: usedFontsDeduped,
     slideCount,
     stats: {