Changes:
- start_ui.sh, start.sh: Check for venv/bin/activate instead of just
venv/ directory to detect Windows venvs in Linux/WSL
- Auto-recreate venv when incompatible platform structure detected
- Add error handling for venv removal, creation, and activation failures
- Provide actionable error messages with distro-specific instructions
- start_ui.bat: Check for venv\Scripts\activate.bat for consistency
with start.bat pattern
Fixes issue where users cloning repo in WSL would encounter:
- "venv/bin/activate: No such file or directory"
- "No module named pip" errors
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
