fix: handle empty/invalid athlete.json in merge, API read, and writer encoding

bincio/extract/writer.py

@@ -382,7 +382,9 @@ def write_athlete_json(summaries: list[dict], output_dir: Path, athlete_config:
         **athlete_config,
     }
     (output_dir / "athlete.json").write_text(
-        json.dumps(athlete, indent=2, ensure_ascii=False)
+        json.dumps(athlete, indent=2, ensure_ascii=False),
+        encoding="utf-8",
+        errors="replace",
     )
 
 

bincio/serve/routers/activities.py

@@ -285,7 +285,10 @@ async def get_athlete(bincio_session: str | None = Cookie(default=None)) -> JSON
     athlete_path = dd / "athlete.json"
     data: dict = {}
     if athlete_path.exists():
+        try:
             data = json.loads(athlete_path.read_text(encoding="utf-8"))
+        except (json.JSONDecodeError, OSError):
+            pass
     # Layer edits/athlete.yaml on top
     edits_path = dd / "edits" / "athlete.yaml"
     if edits_path.exists():