feat(typography): bundle Maple Mono v7.9 as the default font

scripts/prepare-maple-font.py

@@ -0,0 +1,38 @@
+#!/usr/bin/env python3
+"""从指定 v7.9 ZIP 重建本地字体：python3 scripts/prepare-maple-font.py /path/to/MapleMonoNormalNL-NF-CN.zip。
+仅重建字体时需要 fonttools[woff]；应用构建直接使用已入库的 WOFF2。
+来源：https://github.com/subframe7536/maple-font/releases/tag/v7.9
+"""
+import io
+from pathlib import Path
+import sys
+import zipfile
+
+from fontTools import subset
+from fontTools.ttLib import TTFont
+
+root = Path(__file__).resolve().parents[1] / 'web/src/themes'
+output = root / 'fonts/maple'
+output.mkdir(exist_ok=True)
+family = 'Maple Mono Normal NL NF CN'
+css = ['/* Maple Mono v7.9；由 scripts/prepare-maple-font.py 生成，授权见 fonts/maple/LICENSE.txt。 */']
+with zipfile.ZipFile(sys.argv[1]) as archive:
+    (output / 'LICENSE.txt').write_bytes(archive.read('LICENSE.txt'))
+    for variant, weight, style in [('Regular', 400, 'normal'), ('Bold', 700, 'normal'), ('Italic', 400, 'italic'), ('BoldItalic', 700, 'italic')]:
+        data = archive.read('MapleMonoNormalNL-NF-CN-' + variant + '.ttf')
+        source = TTFont(io.BytesIO(data))
+        points = sorted(source.getBestCmap())
+        # 按 Unicode 区间分片，中文和 Nerd Font 不强制随拉丁文字一起下载。
+        for block in sorted({cp // 4096 for cp in points}):
+            unicodes = [cp for cp in points if cp // 4096 == block]
+            font = TTFont(io.BytesIO(data), recalcTimestamp=False)
+            options = subset.Options()
+            options.flavor = 'woff2'
+            subsetter = subset.Subsetter(options=options)
+            subsetter.populate(unicodes=unicodes)
+            subsetter.subset(font)
+            font.flavor = 'woff2'
+            name = f'{variant.lower()}-{block:02x}.woff2'
+            font.save(output / name)
+            css.append(f"@font-face {{ font-family: '{family}'; font-style: {style}; font-weight: {weight}; font-display: swap; src: url('./fonts/maple/{name}') format('woff2'); unicode-range: U+{block * 4096:X}-{(block + 1) * 4096 - 1:X}; }}")
+(root / 'maple-font.css').write_text('\n'.join(css) + '\n')