feat(cli): add shared PDF-to-image rendering and document usage

add shared render_pdf_pages helper for consistent rasterization
reuse the same renderer in regression test and CLI flow
add new render-image CLI command to export PDF pages as PNG
support single-page render (--page) and full export (--all-pages)
add configurable output path and DPI options
document the new rendering command and options in README

generate.py

@@ -10,6 +10,7 @@ import sys
 from pathlib import Path
 
 import click
+from PIL import Image
 
 # Add project root to sys.path so 'src' is importable
 sys.path.insert(0, str(Path(__file__).parent))
@@ -17,6 +18,7 @@ sys.path.insert(0, str(Path(__file__).parent))
 from src.config_loader import load_config
 from src.excel_reader import extract_attendance, extract_persons, extract_year_from_filename
 from src.pdf_filler import fill_pdf
+from src.pdf_render import render_pdf_pages
 from src.validators import show_preview_and_confirm, validate
 
 
@@ -145,5 +147,88 @@ def generate_cmd(excel_file: str, month: str, output_dir: str | None) -> None:
         sys.exit(1)
 
 
+@cli.command("render-image")
+@click.option(
+    "--pdf",
+    "pdf_file",
+    required=True,
+    type=click.Path(exists=True, file_okay=True, dir_okay=False),
+    help="Pfad zur PDF-Datei, die als Bild gerendert werden soll.",
+)
+@click.option(
+    "--out",
+    "output_path",
+    required=False,
+    default=None,
+    type=click.Path(file_okay=True, dir_okay=True),
+    help="Ausgabepfad (Datei für Einzelseite oder Ordner für --all-pages).",
+)
+@click.option(
+    "--dpi",
+    required=False,
+    default=150,
+    show_default=True,
+    type=int,
+    help="Render-Auflösung in DPI.",
+)
+@click.option(
+    "--page",
+    required=False,
+    default=1,
+    show_default=True,
+    type=int,
+    help="1-basierter Seitenindex für Einzelseiten-Render.",
+)
+@click.option(
+    "--all-pages",
+    is_flag=True,
+    default=False,
+    help="Alle Seiten rendern (ignoriert --page).",
+)
+def render_image_cmd(
+    pdf_file: str,
+    output_path: str | None,
+    dpi: int,
+    page: int,
+    all_pages: bool,
+) -> None:
+    """Rendert eine PDF direkt als PNG-Bild(er) über die Regression-Renderfunktion."""
+    pdf_path = Path(pdf_file).resolve()
+    images = render_pdf_pages(pdf_path, dpi=dpi)
+
+    if not images:
+        click.echo("Keine Seiten in der PDF gefunden.", err=True)
+        sys.exit(1)
+
+    if all_pages:
+        if output_path:
+            out_dir = Path(output_path).resolve()
+        else:
+            out_dir = pdf_path.parent / f"{pdf_path.stem}_images"
+        out_dir.mkdir(parents=True, exist_ok=True)
+
+        for idx, img in enumerate(images, start=1):
+            out_file = out_dir / f"{pdf_path.stem}_seite_{idx:02d}.png"
+            Image.fromarray(img).save(out_file)
+            click.echo(f"[OK] {out_file}")
+        return
+
+    if page < 1 or page > len(images):
+        click.echo(
+            f"Ungültige Seite: {page}. PDF hat {len(images)} Seite(n).",
+            err=True,
+        )
+        sys.exit(1)
+
+    if output_path:
+        out_file = Path(output_path).resolve()
+    else:
+        out_file = pdf_path.parent / f"{pdf_path.stem}_seite_{page:02d}.png"
+    out_file.parent.mkdir(parents=True, exist_ok=True)
+
+    Image.fromarray(images[page - 1]).save(out_file)
+    click.echo(f"[OK] {out_file}")
+
+
 if __name__ == "__main__":
     cli()