v0.13: add Quarto/xelatex PDF engine and fix ReportLab wide-table rendering

build_report.py:
- add --engine quarto option: Quarto 1.9 + xelatex pipeline with
  CJK font setup (Source Han Serif/Sans CN via fontspec),
  automatic {.landscape} wrapping for wide tables (>=8 cols),
  TOC/references placeholder replacement, sources.jsonl backfill
- prepare_qmd(): converts Markdown to .qmd with proper YAML front matter,
  writes _preamble.tex for longtable/pdflscape/lscape packages
- _detect_wide_tables(), _build_references_block(): helper functions
- ReportLab path unchanged (remains default)

report-template.py:
- render_table(): force equal-width column distribution for tables
  with >=4 cols or any cell >30 chars, preventing negative availWidth
  crash on mixed CJK/English content
- render_table_blocks(): split long tables (>25 rows) into chunks to
  avoid NoneType comparison crash in ReportLab splitByRow logic

.gitignore:
- add rules for LaTeX temp files (*.aux, xetest.*, *.qmd, _preamble.tex)
- add projects/ to gitignore (research data, not source code)

README.md:
- update status to v0.13
- rewrite PDF section as dual-engine guide with install steps,
  comparison table, and landscape table chunking guidance
- add Quarto troubleshooting (font italic mapping, tlmgr path, param_size)
- add v0.13 to changelog

.opencode/templates/report-template.py

@@ -1085,6 +1085,7 @@ def render_table(md_table: str, styles: StyleSheet1) -> Table:
     - 所有 cell 垂直居中
     - 长文字自动 CJK 换行
     - 长表自动按行分页
+    - 宽表（>=7 列）强制按页宽等分列宽，避免 ReportLab 自动分配失败
     """
     rows: list[list] = []
     raw_rows = []
@@ -1097,28 +1098,90 @@ def render_table(md_table: str, styles: StyleSheet1) -> Table:
         return Table([[""]])
 
     header_cells = raw_rows[0]
+    ncols = len(header_cells)
+
+    # 判断是否需要强制等宽列：
+    # - 列数 >= 4 时（避免自动分配使某列被挤为负宽）
+    # - 或任意单元格文本超过 30 字符（中英文混排时 auto-allocation 不稳定）
+    _max_cell_len = 0
+    for r in raw_rows[1:]:
+        for c in r:
+            if len(c) > _max_cell_len:
+                _max_cell_len = len(c)
+
+    is_wide = ncols >= 4 or _max_cell_len > 30
+    is_very_wide = ncols >= 7 or _max_cell_len > 80
+
+    pad_lr = 2 if is_very_wide else (3 if is_wide else 6)
+    pad_tb = 3 if is_wide else 5
+
     rows.append([
         Paragraph(md_inline_to_rl(c), styles["table-header"]) for c in header_cells
     ])
     for cells in raw_rows[1:]:
-        # 补齐列数（防御性）
-        while len(cells) < len(header_cells):
+        while len(cells) < ncols:
             cells.append("")
         rows.append([_render_table_cell(c, styles) for c in cells])
 
-    table = Table(rows, repeatRows=1, splitByRow=True)
+    # 可用页宽（A4 - margins），给 Table 分配等宽列
+    # 参考 doctemplate 页面宽度：A4.width (595) - left (54) - right (54) ≈ 487 pt
+    # 为安全起见，给表格留一点边距
+    col_widths = None
+    if is_wide:
+        from reportlab.lib.pagesizes import A4
+        avail_width = A4[0] - 110  # A4 宽度 - 两侧边距
+        col_widths = [avail_width / ncols] * ncols
+
+    table = Table(rows, colWidths=col_widths, repeatRows=1, splitByRow=True)
     table.setStyle(TableStyle([
         ("BACKGROUND", (0, 0), (-1, 0), colors.HexColor("#e0e7ff")),
         ("GRID", (0, 0), (-1, -1), 0.5, colors.HexColor("#cbd5e1")),
         ("VALIGN", (0, 0), (-1, -1), "MIDDLE"),
-        ("LEFTPADDING", (0, 0), (-1, -1), 6),
-        ("RIGHTPADDING", (0, 0), (-1, -1), 6),
-        ("TOPPADDING", (0, 0), (-1, -1), 5),
-        ("BOTTOMPADDING", (0, 0), (-1, -1), 5),
+        ("LEFTPADDING", (0, 0), (-1, -1), pad_lr),
+        ("RIGHTPADDING", (0, 0), (-1, -1), pad_lr),
+        ("TOPPADDING", (0, 0), (-1, -1), pad_tb),
+        ("BOTTOMPADDING", (0, 0), (-1, -1), pad_tb),
     ]))
     return table
 
 
+def render_table_blocks(md_table: str, styles: StyleSheet1, max_rows_per_chunk: int = 25) -> list:
+    """Render a markdown table as potentially multiple Table objects.
+
+    When the body has more than ``max_rows_per_chunk`` rows we slice it into
+    smaller chunks (each re-printing the header). This avoids ReportLab's
+    split-by-row bug on very long tables which manifests as
+    ``TypeError: '>' not supported between instances of 'NoneType' and 'NoneType'``.
+    """
+    raw_rows = []
+    for line in md_table.strip().split("\n"):
+        line = line.strip().strip("|")
+        cells = [c.strip() for c in line.split("|")]
+        raw_rows.append(cells)
+    if not raw_rows:
+        return [Table([[""]])]
+
+    header = raw_rows[0]
+    body = raw_rows[1:]
+    if len(body) <= max_rows_per_chunk:
+        return [render_table(md_table, styles)]
+
+    # Split into chunks
+    out = []
+    from reportlab.platypus import Spacer
+    for start in range(0, len(body), max_rows_per_chunk):
+        chunk = body[start:start + max_rows_per_chunk]
+        lines_md = [
+            "| " + " | ".join(header) + " |",
+            "|" + "|".join(["---"] * len(header)) + "|",
+        ]
+        for row in chunk:
+            lines_md.append("| " + " | ".join(row) + " |")
+        out.append(render_table("\n".join(lines_md), styles))
+        out.append(Spacer(1, 4))
+    return out
+
+
 def _render_generic_block(block: Block, story: list, base_dir: Path, styles: StyleSheet1, *, in_summary: bool) -> None:
     """渲染一个非 H1/H2 的 block（p/quote/bullet/hr/image/table/h3）。
 
@@ -1157,7 +1220,8 @@ def _render_generic_block(block: Block, story: list, base_dir: Path, styles: Sty
             ))
     elif block.kind == "table":
         try:
-            story.append(render_table(block.content, styles))
+            for _tbl_block in render_table_blocks(block.content, styles):
+                story.append(_tbl_block)
         except Exception as e:
             story.append(Paragraph(f"[表格渲染失败: {e}]", styles["caption"]))