fix(#179): Scorecard via WeasyPrint-PDF (Container hat kein Chromium)

Container hat keine Playwright/Chromium-Installation — PNG-Render
deferred. WeasyPrint-PDF mit exaktem Seiten-Setup (1200x630pt fuer
og, 1080x1080pt fuer square) liefert jetzt /api/assessment/scorecard.pdf.

Folge-Issue fuer PNG: Chromium ins Image bauen oder pypdfium2/pdf2image
fuer pdf→png-Konvertierung ergaenzen.

app/main.py

@@ -3413,50 +3413,67 @@ async def scorecard_template(
     })
 
 
-@app.get("/api/assessment/scorecard.png")
-async def api_scorecard_png(
+@app.get("/api/assessment/scorecard.pdf")
+async def api_scorecard_pdf(
     drucksache: str, bundesland: str = "NRW", format: str = "og",
 ):
-    """Liefert die Scorecard als PNG via Playwright-Render (#179).
+    """Liefert die Scorecard als PDF via WeasyPrint (#179).
 
-    `format=og` → 1200×630, `format=square` → 1080×1080.
+    `format=og` → 1200×630pt, `format=square` → 1080×1080pt.
+
+    PNG-Render via Playwright wird in einem Folge-Issue ergänzt
+    (Container hat heute kein Chromium installiert).
     """
+    from fastapi.responses import Response as _Response
+    from weasyprint import HTML, CSS
     drucksache = validate_drucksache(drucksache)
     row = await get_assessment(drucksache)
     if not row:
         raise HTTPException(status_code=404, detail="Antrag nicht gefunden")
-
     if format not in ("og", "square"):
         raise HTTPException(status_code=400, detail="format muss 'og' oder 'square' sein")
+
     width, height = ((1200, 630) if format == "og" else (1080, 1080))
 
+    # HTML aus dem internen Template ziehen (gleiche Logik wie /v2/scorecard).
+    from .models import Assessment
+    assessment = Assessment.model_validate(row)
+    matrix_lookup = {e.field: {"rating": e.rating} for e in assessment.gwoe_matrix}
+    fraktionen = list(row.get("fraktionen", []) or [])
+    if isinstance(fraktionen, str):
         try:
-        from playwright.sync_api import sync_playwright
-        import urllib.parse as _up
-        url = (
-            f"http://127.0.0.1:{settings.port}/v2/scorecard"
-            f"?drucksache={_up.quote(drucksache, safe='')}"
-            f"&bundesland={_up.quote(bundesland)}"
-            f"&format={format}"
-        )
-        with sync_playwright() as pw:
-            browser = pw.chromium.launch(args=["--no-sandbox"])
-            page = browser.new_page(viewport={"width": width, "height": height})
-            page.goto(url, wait_until="networkidle", timeout=15000)
-            png = page.screenshot(
-                clip={"x": 0, "y": 0, "width": width, "height": height}, type="png",
-            )
-            browser.close()
-    except Exception as e:
-        logger.exception("Scorecard-Render fehlgeschlagen")
-        raise HTTPException(status_code=500, detail=f"Render-Fehler: {e}")
+            import json as _json
+            fraktionen = _json.loads(fraktionen) or []
+        except Exception:
+            fraktionen = []
 
+    score = assessment.gwoe_score
+    if   score >= 8: score_color = "#1a7f37"
+    elif score >= 5: score_color = "#bf6c10"
+    else:            score_color = "#9a2a2a"
+
+    template = templates.env.get_template("v2/screens/scorecard.html")
+    html_content = template.render(
+        request=None,
+        assessment=assessment,
+        bundesland=bundesland,
+        matrix_lookup=matrix_lookup,
+        fraktionen=fraktionen[:4],
+        datum=(row.get("datum") or "")[:10],
+        score_color=score_color,
+        width=width,
+        height=height,
+    )
+
+    # PDF mit exakt einer Seite in der Zielgrösse
+    page_size_css = f"@page {{ size: {width}px {height}px; margin: 0; }}"
+    pdf = HTML(string=html_content).write_pdf(stylesheets=[CSS(string=page_size_css)])
     safe_name = drucksache.replace("/", "-")
-    return Response(
-        content=png, media_type="image/png",
+    return _Response(
+        content=pdf, media_type="application/pdf",
         headers={
             "Content-Disposition": (
-                f'inline; filename="scorecard-{safe_name}-{format}.png"'
+                f'inline; filename="scorecard-{safe_name}-{format}.pdf"'
             ),
             "Cache-Control": "public, max-age=600",
         },