Fix overlapping text and improve Arabic rendering in PDFs

Update PDF rendering logic to use fontkit for Arabic shaping and RTL reordering, eliminating pre-shaping and resolving text overlap issues.

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artifacts/api-server/tests/executive-meetings.test.mjs

@@ -1024,15 +1024,19 @@ test("PDF content: title label, rowColor tint, dropped isHighlighted, fontColor"
   void ascii;
 });
 
-test("PDF Arabic shaping: title renders in connected presentation forms (not isolated)", async () => {
+test("PDF Arabic shaping: title renders in connected, correctly-ordered Arabic", async () => {
   // Regression for the bug where Arabic in the printed PDF appeared as
-  // disconnected, visually-reversed letters (e.g. "الاجتماعات" →
-  // "تاعامتجالا"). PDFKit has no built-in HarfBuzz, so we now run a
-  // pre-shaping pass that converts base Arabic letters (U+0600..U+06FF)
-  // to their contextual presentation forms (FE80..FEFF, plus FEFB
-  // lam-alef ligature) BEFORE handing text to bidi + PDFKit. We assert
-  // the rendered PDF contains presentation-form codepoints in its
-  // embedded ToUnicode CMap (proves shaped glyphs were drawn).
+  // disconnected, visually-reversed letters (e.g. "قائمة حضور" →
+  // "ةمئاقروضح"). The renderer now hands RAW Unicode (logical order,
+  // U+0600..06FF base letters) to PDFKit, which forwards it to fontkit
+  // along with `features: ['rtla', 'rclt', 'calt', 'liga', ...]`.
+  // Fontkit performs shaping AND visual right-to-left reorder at the
+  // glyph layer, so the PDF content stream contains glyph IDs, not
+  // characters. Per PDF 1.7 §9.10, every embedded TrueType font carries
+  // a ToUnicode CMap that maps each emitted glyph back to its LOGICAL
+  // base codepoint — that is what we assert here. (Pre-shaped output
+  // would put U+FExx presentation-form codepoints in the CMap; the
+  // current pipeline must NOT do that.)
 
   // End-to-end: render a real PDF and assert the inflated streams
   // (which include the embedded ToUnicode CMap) reference at least one
@@ -1081,13 +1085,25 @@ test("PDF Arabic shaping: title renders in connected presentation forms (not iso
     cursor = end + "\nendstream".length;
   }
   const allDecoded = decoded.join("\n");
-  // Match any FE80..FEFF or FB50..FDFF hex literal — these are the
-  // Arabic Presentation Forms ranges. Without shaping none would appear.
-  const presFormsRegex = /<(?:FE[89A-F][0-9A-F]|FEF[0-9A-F]|FE[7][0-9A-F]|FB[5-9A-F][0-9A-F]|FC[0-9A-F]{2}|FD[0-9A-F]{2})>/i;
+  // Assert (a) the embedded ToUnicode CMap references at least one base
+  // Arabic codepoint (U+0600..06FF) — proves Arabic content was drawn
+  // and survived round-tripping — and (b) the CMap does NOT reference
+  // any Arabic Presentation Forms (FE70..FEFF / FB50..FDFF). The
+  // presence of presentation-form codepoints in the CMap would mean
+  // someone re-introduced the pre-shaping pass and the PDF would
+  // render visually mirrored again.
+  const baseArabicRegex = /<(?:06[0-9A-F]{2})>/i;
   assert.match(
     allDecoded,
-    presFormsRegex,
-    "rendered PDF must reference Arabic Presentation Forms codepoints (proves shaping ran before PDFKit)",
+    baseArabicRegex,
+    "rendered PDF must reference base Arabic codepoints in its ToUnicode CMap",
+  );
+  const presFormsRegex = /<(?:FE[789A-F][0-9A-F]|FB[5-9A-F][0-9A-F]|FC[0-9A-F]{2}|FD[0-9A-F]{2})>/i;
+  const presMatch = allDecoded.match(presFormsRegex);
+  assert.equal(
+    presMatch,
+    null,
+    `rendered PDF must NOT reference Arabic Presentation Forms in its ToUnicode CMap — found ${presMatch?.[0]} (regression: pre-shaping has been re-introduced and the PDF will render visually mirrored)`,
   );
 });