refactor: split build-docs.js into focused lib modules

scripts/lib/alerts.css

@@ -0,0 +1,41 @@
+/* Alert callout styles for GitHub GFM > [!NOTE] / [!TIP] / etc. */
+.markdown-alert {
+  padding: 0.5rem 1rem;
+  margin-bottom: 16px;
+  border-left: 0.25em solid;
+  border-radius: 6px;
+}
+.markdown-alert > :first-child { margin-top: 0; }
+.markdown-alert > :last-child { margin-bottom: 0; }
+.markdown-alert-title {
+  display: flex;
+  align-items: center;
+  font-weight: 600;
+  margin-bottom: 4px;
+}
+.markdown-alert-title svg { margin-right: 8px; }
+.markdown-alert-note {
+  border-color: var(--borderColor-accent-emphasis, #0969da);
+  background-color: var(--bgColor-accent-muted, #ddf4ff);
+}
+.markdown-alert-note .markdown-alert-title { color: var(--fgColor-accent, #0969da); }
+.markdown-alert-tip {
+  border-color: var(--borderColor-success-emphasis, #1a7f37);
+  background-color: var(--bgColor-success-muted, #dafbe1);
+}
+.markdown-alert-tip .markdown-alert-title { color: var(--fgColor-success, #1a7f37); }
+.markdown-alert-important {
+  border-color: var(--borderColor-done-emphasis, #8250df);
+  background-color: var(--bgColor-done-muted, #fbefff);
+}
+.markdown-alert-important .markdown-alert-title { color: var(--fgColor-done, #8250df); }
+.markdown-alert-warning {
+  border-color: var(--borderColor-attention-emphasis, #9a6700);
+  background-color: var(--bgColor-attention-muted, #fff8c5);
+}
+.markdown-alert-warning .markdown-alert-title { color: var(--fgColor-attention, #9a6700); }
+.markdown-alert-caution {
+  border-color: var(--borderColor-danger-emphasis, #d1242f);
+  background-color: var(--bgColor-danger-muted, #ffebe9);
+}
+.markdown-alert-caution .markdown-alert-title { color: var(--fgColor-danger, #d1242f); }

scripts/lib/docs-css.js

@@ -0,0 +1,41 @@
+'use strict';
+
+const fs = require('fs');
+const path = require('path');
+const { prefixCssSelectors } = require('./utils');
+
+// Generate alert callout CSS for marked-alert GFM rendering
+function generateAlertsCss() {
+  return fs.readFileSync(path.join(__dirname, 'alerts.css'), 'utf8');
+}
+
+// Generate highlight.js syntax highlighting CSS (GitHub light + dark themes).
+// The dark theme rules are scoped to the data-color-mode="dark" attribute and
+// to the prefers-color-scheme: dark media query for data-color-mode="auto".
+function generateHljsCss() {
+  const hljsStylesDir = path.join(__dirname, '..', '..', 'node_modules', 'highlight.js', 'styles');
+  const hljsLightCss = fs.readFileSync(path.join(hljsStylesDir, 'github.min.css'), 'utf8');
+  const hljsDarkCss = fs.readFileSync(path.join(hljsStylesDir, 'github-dark.min.css'), 'utf8');
+  return [
+    '/* highlight.js \u2013 GitHub light theme (default) */',
+    hljsLightCss,
+    '',
+    '/* highlight.js \u2013 GitHub Dark theme (terminal blocks) */',
+    prefixCssSelectors(hljsDarkCss, '.terminal-block'),
+    '',
+    '/* highlight.js \u2013 GitHub Dark theme (explicit dark mode) */',
+    prefixCssSelectors(hljsDarkCss, 'html[data-color-mode="dark"]'),
+    '',
+    '/* highlight.js \u2013 GitHub Dark theme (system dark preference) */',
+    '@media (prefers-color-scheme: dark) {',
+    prefixCssSelectors(hljsDarkCss, 'html[data-color-mode="auto"]'),
+    '}',
+  ].join('\n');
+}
+
+// Generate docs CSS \u2013 link discoverability and workshop SPA styles
+function generateDocsCss() {
+  return fs.readFileSync(path.join(__dirname, 'docs.css'), 'utf8');
+}
+
+module.exports = { generateAlertsCss, generateHljsCss, generateDocsCss };