security: sanitize personal paths and usernames from documentation

Replaced all instances of:
- /home/dell/coding/giglez → /path/to/giglez
- /home/dell → ~
- leetcrypt → your-username
- PreistlyPython → your-username
- dell@ → user@

Affected files:
- 17 documentation files in docs/
- 2 shell scripts (download_rf_test_datasets.sh, start_web.sh)

No functional changes, only path/username sanitization for privacy.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

docs/INSTALLATION_GUIDE.md

@@ -6,7 +6,7 @@
 
 ```bash
 # Navigate to project directory
-cd /home/dell/coding/giglez
+cd /path/to/giglez
 
 # Create virtual environment and install all dependencies
 ./scripts/safe_install.sh --create-venv
@@ -31,7 +31,7 @@ That's it! The script handles everything automatically.
 #### 1. **Create Virtual Environment**
 
 ```bash
-cd /home/dell/coding/giglez
+cd /path/to/giglez
 
 # Create venv
 python3 -m venv venv
@@ -381,7 +381,7 @@ pytest tests/test_parser.py
 
 ```bash
 # Every time you work on the project:
-cd /home/dell/coding/giglez
+cd /path/to/giglez
 source venv/bin/activate
 
 # Verify activation