Init photobooth - borne photo evenementielle RPi4

Backend FastAPI complet : camera gphoto2, filtres/overlays Pillow,
chroma key OpenCV, multi-shot/collage, GIF, impression CUPS, email SMTP,
QR code. Frontend web vanilla (HTML/CSS/JS) pour Chromium kiosk.
Menu admin cache (appui long coin ecran). Toutes les fonctionnalites
activables/desactivables. Scripts install + systemd pour RPi4.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

backend/printer.py

@@ -0,0 +1,81 @@
+import logging
+from pathlib import Path
+
+from backend.config import charger_config
+
+log = logging.getLogger("photobooth.printer")
+
+# Essayer d'importer cups
+try:
+    import cups
+    CUPS_DISPONIBLE = True
+except ImportError:
+    CUPS_DISPONIBLE = False
+    log.warning("pycups non installe, impression indisponible")
+
+
+def lister_imprimantes() -> list[dict]:
+    """Liste les imprimantes disponibles via CUPS."""
+    if not CUPS_DISPONIBLE:
+        return [{"nom": "[Simulation] Imprimante virtuelle", "statut": "prete"}]
+
+    try:
+        conn = cups.Connection()
+        imprimantes = conn.getPrinters()
+        return [
+            {
+                "nom": nom,
+                "statut": "prete" if info.get("printer-state") == 3 else "occupee",
+                "info": info.get("printer-info", ""),
+            }
+            for nom, info in imprimantes.items()
+        ]
+    except cups.IPPError as e:
+        log.error(f"Erreur CUPS : {e}")
+        return []
+
+
+def imprimer(chemin_photo: Path, imprimante: str | None = None, copies: int | None = None) -> bool:
+    """Imprime une photo sur l'imprimante configuree."""
+    config = charger_config()
+    conf_imp = config.get("impression", {})
+
+    if imprimante is None:
+        imprimante = conf_imp.get("imprimante")
+    if copies is None:
+        copies = conf_imp.get("copies", 1)
+
+    if not chemin_photo.exists():
+        log.error(f"Fichier introuvable : {chemin_photo}")
+        return False
+
+    if not CUPS_DISPONIBLE:
+        log.info(f"[Simulation] Impression de {chemin_photo} x{copies}")
+        return True
+
+    try:
+        conn = cups.Connection()
+
+        if imprimante is None:
+            imprimante = conn.getDefault()
+            if imprimante is None:
+                imprimantes = conn.getPrinters()
+                if imprimantes:
+                    imprimante = list(imprimantes.keys())[0]
+                else:
+                    log.error("Aucune imprimante trouvee")
+                    return False
+
+        options = {
+            "copies": str(copies),
+            "media": conf_imp.get("format", "10x15"),
+            "fit-to-page": "true",
+        }
+
+        job_id = conn.printFile(imprimante, str(chemin_photo), "Photobooth", options)
+        log.info(f"Impression lancee : job #{job_id} sur {imprimante}")
+        return True
+
+    except cups.IPPError as e:
+        log.error(f"Erreur impression : {e}")
+        return False