Add README, MIT license and .gitignore

README documents the reverse-tunnel use case, features, security model and
usage steps. .gitignore excludes OS/editor cruft and prevents accidental
commit of generated WireGuard configs (which contain private keys).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,24 @@
+# OS
+.DS_Store
+Thumbs.db
+desktop.ini
+
+# Editor / IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+*~
+.claude/
+
+# Temp files
+*.tmp
+*.bak
+*.log
+
+# Generated WireGuard configs (sollten nicht ins Repo)
+*.conf
+!example.conf
+
+# Saved tokens (verschlüsselt, aber trotzdem nichts fürs Repo)
+*.token