SnapOtter: recreate the AI venv with --clear

The venv lives in the data directory and is recreated on every update; uv now refuses a non-empty path.

ct/snapotter.sh

@@ -86,7 +86,7 @@ EOF
 
     msg_info "Updating SnapOtter"
     $STD uv python install 3.11
-    $STD uv venv --seed --python 3.11 /opt/snapotter_data/ai/venv
+    $STD uv venv --clear --seed --python 3.11 /opt/snapotter_data/ai/venv
     if [[ "$(arch_resolve)" == "arm64" ]]; then
       $STD uv pip install --python /opt/snapotter_data/ai/venv/bin/python \
         numpy==1.26.4 Pillow==12.3.0 opencv-python-headless==4.10.0.84 fonttools \