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/ML_IMPROVEMENTS_RESEARCH.md

@@ -32,7 +32,7 @@ GigLez currently uses a **multi-strategy pattern-based decoder** with two comple
 - **Protocol Database Matching**: Compares against known protocol signatures
 - **Confidence Scoring**: Weighted combination of timing accuracy (40%), bit count match (30%), pattern match (30%)
 
-**Code Location:** `/home/dell/coding/giglez/src/matcher/pattern_decoder.py:73-401`
+**Code Location:** `/path/to/giglez/src/matcher/pattern_decoder.py:73-401`
 
 #### **Strategy 2: RTL_433 Decoder** (`src/matcher/rtl433_decoder.py`)
 - **Subprocess Wrapper**: Converts `.sub` files to RTL_433 pulse format
@@ -41,7 +41,7 @@ GigLez currently uses a **multi-strategy pattern-based decoder** with two comple
 - **JSON Parsing**: Extracts device model, manufacturer, ID, and raw sensor data
 - **High Confidence**: RTL_433 matches assigned 0.95 confidence (established protocols)
 
-**Code Location:** `/home/dell/coding/giglez/src/matcher/rtl433_decoder.py:58-335`
+**Code Location:** `/path/to/giglez/src/matcher/rtl433_decoder.py:58-335`
 
 ### 1.2 Strengths