fix(export): v4.7.3 tableaux + emojis en PDF/HTML

- Tableaux GFM rendus comme texte brut dans les exports HTML/PDF. Ajout d'un
  parseur de tableaux pipe (bloc 'table') + rendu <table> (thead/tbody,
  alignement gauche/centre/droite, bordures .ftable) dans blocks_to_html;
  blocks_to_markdown reconstruit un tableau pipe valide.
- Emojis 'carrés noirs' en PDF: xhtml2pdf n'embarque que des polices de base
  sans glyphes emoji. Moteur PDF -> WeasyPrint (tables CSS + emojis couleur via
  pango + fonts-noto-color-emoji installes dans l'image). Repli automatique sur
  xhtml2pdf quand weasyprint n'a pas ses libs natives (dev Windows).
- Dockerfile: libs weasyprint (pango/harfbuzz/gdk-pixbuf/shared-mime-info) +
  fonts-dejavu-core + fonts-noto-color-emoji. requirements: + weasyprint==69.0.
- Verifie en reel sur README.md: HTML = <table class=ftable> (thead/th, center);
  PDF 10 pages, texte de table present, Noto-Color-Emoji embarque + pixels
  colores confirmes. 199/199 tests (4 nouveaux).

tests/test_app.py

@@ -3165,5 +3165,73 @@ def test_v472_binary_file_page_not_exported(client, monkeypatch, tmp_path):
         md = page_to_markdown(_load(pid), include_children=False)
         assert "# manual.pdf" in md
         assert "fake binary" not in md  # never dump binary into markdown
+    finally:
+        _cleanup_src(pid, uid)
+
+
+_TABLE_MD = (
+    "# Titre\n\n"
+    "| ID | Nom | Score | Statut |\n"
+    "|----|:---:|------:|--------|\n"
+    "| 1  | Alice | 95.5 | ✅ Actif |\n"
+    "| 2  | Bob | 87.2 | 🟡 En attente |\n"
+    "| 3  | Charlie | 99.9 | ❌ Inactif |\n"
+)
+
+
+def test_v472_table_md_renders_real_html_table(client):
+    """A GFM pipe table becomes a real <table> (header + cells + alignment)."""
+    from app.services.export import _page_blocks, blocks_to_html
+    pid, uid = _make_src_page(raw_md=_TABLE_MD, title="Table Page")
+    try:
+        blocks = _page_blocks(_load(pid))
+        tables = [b for b in blocks if b.get("type") == "table"]
+        assert tables, "expected a parsed table block"
+        t = tables[0]
+        assert t["align"] == ["left", "center", "right", "left"]
+        html = blocks_to_html(blocks)
+        assert "<table" in html
+        assert "<thead>" in html and "<th>" in html
+        assert "<tbody>" in html and "<td>" in html
+        assert 'text-align:center;' in html
+        assert "Alice" in html and "✅ Actif" in html
+    finally:
+        _cleanup_src(pid, uid)
+
+
+def test_v472_table_md_standalone_html_has_table_css(client):
+    """Standalone HTML export embeds the table and its stylesheet class."""
+    from app.services.export import page_to_standalone_html
+    pid, uid = _make_src_page(raw_md=_TABLE_MD, title="Table Page")
+    try:
+        html = page_to_standalone_html(_load(pid), include_children=False)
+        assert 'class="ftable"' in html
+        assert "Alice" in html
+        assert "Charlie" in html
+    finally:
+        _cleanup_src(pid, uid)
+
+
+def test_v472_table_markdown_roundtrip(client):
+    """A table block is re-emitted as a valid pipe table with a separator."""
+    from app.services.export import _page_blocks, blocks_to_markdown
+    pid, uid = _make_src_page(raw_md=_TABLE_MD, title="Table Page")
+    try:
+        md = blocks_to_markdown(_page_blocks(_load(pid)))
+        assert "| ID | Nom | Score | Statut |" in md
+        assert ":---:" in md and "---:" in md
+        assert "| 3 | Charlie" in md
+    finally:
+        _cleanup_src(pid, uid)
+
+
+def test_v472_table_in_pdf(client, monkeypatch, tmp_path):
+    """PDF export of a markdown table page returns a valid PDF (any engine)."""
+    from app.services.export import page_to_pdf_bytes
+    pid, uid = _make_src_page(raw_md=_TABLE_MD, title="Table Page")
+    try:
+        pdf = page_to_pdf_bytes(_load(pid))
+        assert pdf[:5] == b"%PDF-"
+        assert len(pdf) > 1000
     finally:
         _cleanup_src(pid, uid)