docs: update CLI commands to use python -m rf_mapper

- Replace rf-mapper with python -m rf_mapper throughout docs
- Add note about activating venv first
- Updated: CLAUDE.md, PROJECT.md, USAGE.md, CHEATSHEET.md, HOME_ASSISTANT.md

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

PROJECT.md

@@ -122,14 +122,17 @@ pip install -e .
 ## Quick Start
 
 ```bash
+# Activate virtual environment
+source venv/bin/activate
+
 # Start web server (background)
-rf-mapper start
+python -m rf_mapper start
 
 # Check status
-rf-mapper status
+python -m rf_mapper status
 
 # CLI scan
-rf-mapper scan
+python -m rf_mapper scan
 
 # Open http://localhost:5000
 ```