fix htmx refactor route mismatches and remaining TODO items

- wireguard: POST /peers with JSON encoding (was /add-peer)
- rules: delete by rule_id in URL path (was JSON body); pass rule objects with id from server; add hx-disable to initial render
- nat: port forward delete uses URL path params to match blueprint
- nat: masquerade toggle uses native hx-post/hx-vals (was inline fetch)
- app.js renderers updated to use URL path deletes for rules and forwards
- remove TODO.md

.gitignore

@@ -15,8 +15,7 @@ __pycache__/
 # Local AI tool config (contains internal hostnames)
 opencode.json
 
-# Runtime data configs (source-of-truth for services)
-config/dnsmasq/config.json
-config/nginx/config.json
-config/wireguard/config.json
-data/nginx/sites-enabled/
+# Runtime artifacts
+build/
+config/
+data/