Clean rules database and add documentation

- Remove OCR noise, credits, and duplicates from rules-database.json (288→255 rules)
- Add clean_rules.py script for rule cleanup
- Add CLAUDE.md, docs/, and update README with documentation links

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

docs/.gitignore

@@ -0,0 +1,16 @@
+# Generated docs
+*.generated.md
+*.backup.md
+
+# Environment files
+.env
+.env.local
+
+# IDE files
+.idea/
+.vscode/
+*.swp
+*.swo
+
+# Logs
+*.log