fix: PaddleOCR 3.4.0 compatibility — use lang=en with PP-OCRv5

PaddleOCR 3.4.0 removed 'latin' language support, causing ValueError
at startup. Now uses lang='en' with ocr_version='PP-OCRv5' and falls
back to lang='latin' for older PaddleOCR versions.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

paddleocr-service/main.py

@@ -1,4 +1,4 @@
-"""PaddleOCR Remote Service — PP-OCRv4 Latin auf x86_64."""
+"""PaddleOCR Remote Service — PP-OCRv5 Latin auf x86_64."""
 
 import io
 import logging
@@ -24,11 +24,20 @@ def get_engine():
         from paddleocr import PaddleOCR
 
         logger.info("Loading PaddleOCR model...")
-        _engine = PaddleOCR(
-            lang="latin",
-            use_angle_cls=True,
-            show_log=False,
-        )
+        # PaddleOCR >= 3.x: use ocr_version param; fallback for older API
+        try:
+            _engine = PaddleOCR(
+                lang="en",
+                ocr_version="PP-OCRv5",
+                use_angle_cls=True,
+                show_log=False,
+            )
+        except (ValueError, TypeError):
+            _engine = PaddleOCR(
+                lang="latin",
+                use_angle_cls=True,
+                show_log=False,
+            )
         logger.info("PaddleOCR model loaded successfully")
     return _engine
 
@@ -48,7 +57,7 @@ def startup_load_model():
 @app.get("/health")
 def health():
     if _ready:
-        return {"status": "ok", "model": "PP-OCRv4-latin"}
+        return {"status": "ok", "model": "PP-OCRv5-latin"}
     return {"status": "loading"}