fix: force UTF-8 env for child processes in suite runner

Force PYTHONIOENCODING=utf-8 (instead of setdefault) so an inherited
non-UTF-8 value cannot conflict with the parent's UTF-8 output decoder
and corrupt captured reports (per Greptile review). Also set PYTHONUTF8=1
to enable UTF-8 Mode, covering child-side file I/O on Windows (per Gemini
review).

Co-authored-by: Mervin Praison <[email protected]>

src/praisonai/praisonai/suite_runner/runner.py

@@ -71,8 +71,11 @@ class ScriptRunner:
         # Apply overrides
         env.update(self.env_overrides)
 
-        # Ensure child Python processes emit UTF-8 on Windows (avoid cp1252 decode errors)
-        env.setdefault("PYTHONIOENCODING", "utf-8")
+        # Ensure child Python processes emit UTF-8 on Windows (avoid cp1252 decode errors).
+        # Force (not setdefault) so an inherited non-UTF-8 value can't corrupt the parent's
+        # UTF-8 decoding of captured output. PYTHONUTF8 also covers child-side file I/O.
+        env["PYTHONIOENCODING"] = "utf-8"
+        env["PYTHONUTF8"] = "1"
 
         return env