Render rich text, links, and special characters correctly in PDF exports

PDF exports now preserve bold/italic/links/lists/blockquotes from the
description editor (via a new HTML block/run parser) instead of flattening
to plain text. Literal "[text](url)" links inserted by the editor's Link
button are converted to real <a> tags before rendering. Tabs and common
"smart typography" characters (smart quotes, dashes, ellipsis, bullet) are
mapped to their WinAnsiEncoding glyphs instead of rendering as "?".

Co-Authored-By: Claude Sonnet 4.6 <[email protected]>

core/htmlblocks.js

@@ -0,0 +1,125 @@
+'use strict';
+
+const { decodeEntities } = require('./util');
+
+/**
+ * Parse sanitized description HTML (see core/sanitize.js) into a flat list
+ * of blocks with inline formatting runs, for renderers (PDF) that need to
+ * preserve bold/italic/links/lists rather than flattening to plain text.
+ *
+ * Each block: { type, runs, indent, n? }
+ *   type:   'p' | 'h1'..'h4' | 'blockquote' | 'li' | 'oli' | 'hr'
+ *   runs:   [{ text, bold, italic, code, href }] (absent for 'hr')
+ *   indent: list/quote nesting depth (0 = top level)
+ *   n:      list item number, only for 'oli'
+ */
+
+const TAG_RE = /<\s*(\/?)\s*([a-zA-Z][a-zA-Z0-9]*)((?:"[^"]*"|'[^']*'|[^>"'])*)>/g;
+const HREF_RE = /href\s*=\s*"([^"]*)"|href\s*=\s*'([^']*)'/i;
+
+function htmlToBlocks(html) {
+  const blocks = [];
+  let current = null;
+  const styleStack = [{}];
+  const context = []; // nesting of <ul>/<ol>/<blockquote>
+
+  const indentLevel = () => context.length;
+  const currentStyle = () => styleStack[styleStack.length - 1];
+
+  const flushBlock = () => {
+    if (!current) return;
+    if (current.type === 'hr' || current.runs.some((r) => r.text.trim() !== '')) blocks.push(current);
+    current = null;
+  };
+  const startBlock = (type, extra = {}) => {
+    flushBlock();
+    current = { type, runs: [], indent: indentLevel(), ...extra };
+  };
+  const pushText = (text) => {
+    if (!text) return;
+    if (!current) current = { type: 'p', runs: [], indent: indentLevel() };
+    current.runs.push({ text, ...currentStyle() });
+  };
+
+  let last = 0;
+  let m;
+  while ((m = TAG_RE.exec(html)) !== null) {
+    if (m.index > last) pushText(decodeEntities(html.slice(last, m.index)));
+    last = TAG_RE.lastIndex;
+    const closing = Boolean(m[1]);
+    const tag = m[2].toLowerCase();
+    const rawAttrs = m[3];
+
+    switch (tag) {
+      case 'p':
+      case 'div':
+        if (closing) flushBlock();
+        else startBlock('p');
+        break;
+      case 'h1':
+      case 'h2':
+      case 'h3':
+      case 'h4':
+        if (closing) flushBlock();
+        else startBlock(tag);
+        break;
+      case 'blockquote':
+        if (closing) { flushBlock(); context.pop(); }
+        else { context.push({ kind: 'blockquote' }); startBlock('blockquote'); }
+        break;
+      case 'ul':
+      case 'ol':
+        if (closing) context.pop();
+        else context.push({ kind: tag, counter: 0 });
+        break;
+      case 'li':
+        if (closing) flushBlock();
+        else {
+          const ctx = context[context.length - 1];
+          const depth = Math.max(0, indentLevel() - 1);
+          if (ctx && ctx.kind === 'ol') { ctx.counter += 1; startBlock('oli', { n: ctx.counter, indent: depth }); }
+          else startBlock('li', { indent: depth });
+        }
+        break;
+      case 'br':
+        flushBlock();
+        break;
+      case 'hr':
+        flushBlock();
+        blocks.push({ type: 'hr' });
+        break;
+      case 'b':
+      case 'strong':
+        if (closing) styleStack.pop();
+        else styleStack.push({ ...currentStyle(), bold: true });
+        break;
+      case 'i':
+      case 'em':
+        if (closing) styleStack.pop();
+        else styleStack.push({ ...currentStyle(), italic: true });
+        break;
+      case 'code':
+      case 'pre':
+        if (closing) styleStack.pop();
+        else styleStack.push({ ...currentStyle(), code: true });
+        break;
+      case 'a':
+        if (closing) styleStack.pop();
+        else {
+          const hrefM = HREF_RE.exec(rawAttrs);
+          styleStack.push({ ...currentStyle(), href: hrefM ? (hrefM[1] ?? hrefM[2]) : undefined });
+        }
+        break;
+      default:
+        // Unrecognized/transparent allowed tags (table*, span, u, s, sub, sup):
+        // no block or style change.
+        break;
+    }
+  }
+  pushText(decodeEntities(html.slice(last)));
+  flushBlock();
+
+  return blocks;
+}
+
+module.exports = { htmlToBlocks };