Fix logging: use basicConfig(force=True) to override Streamlit's WARNING-level root config

Streamlit sets root logger level=WARNING before app.py executes. Our previous
if-not-handlers guard was skipped once Streamlit's server added its own handler,
leaving all INFO messages silently dropped. force=True removes existing handlers
and guarantees INFO+ output to stderr in HF Spaces logs.

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

utils/logger.py

@@ -1,17 +1,15 @@
 import logging
 import sys
 
-_FMT = "[%(asctime)s] [%(levelname)s] %(name)s: %(message)s"
-_DATE_FMT = "%Y-%m-%d %H:%M:%S"
-
-# Configure root logger once so every module that calls
-# logging.getLogger(__name__) outputs to stdout (visible in HF Spaces logs).
-_root = logging.getLogger()
-if not _root.handlers:
-    _handler = logging.StreamHandler(sys.stdout)
-    _handler.setFormatter(logging.Formatter(_FMT, datefmt=_DATE_FMT))
-    _root.addHandler(_handler)
-    _root.setLevel(logging.INFO)
+# force=True (Python 3.8+) removes any handlers already added by Streamlit's
+# server startup before app.py loads, and guarantees our format + level win.
+logging.basicConfig(
+    level=logging.INFO,
+    format="[%(asctime)s] [%(levelname)s] %(name)s: %(message)s",
+    datefmt="%Y-%m-%d %H:%M:%S",
+    stream=sys.stderr,
+    force=True,
+)
 
 # Named app logger for explicit imports (from utils.logger import logger)
 logger = logging.getLogger("kasper")