Add .gitignore, update app.py and config.py, remove stale docs

.gitignore

@@ -0,0 +1,20 @@
+# Python
+__pycache__/
+*.py[cod]
+*.pyo
+
+# Runtime data (device-specific, contains IPs and sensitive config)
+data/config.txt
+data/device_info.txt
+data/log.txt
+data/tag.txt
+data/idmasa.txt
+
+# Offline wheel cache (large, OS-specific)
+Files/reposytory/
+Files/system_packages/
+
+# Misc
+.lgd-nfy0
+.DS_Store
+Thumbs.db