Add panel-api and panelctl scripts for container management

Co-authored-by: Copilot <copilot@github.com>

API.md

@@ -0,0 +1,48 @@
+# panel-api
+
+A tiny local HTTP API wrapper around panelctl for future frontend integration.
+
+The service now also serves a lightweight web UI at `/`.
+
+Default bind:
+- 127.0.0.1:9911
+
+## Endpoints
+
+- GET /health
+- GET /
+- GET /apps
+- GET /apps/<name>
+- POST /apps/init
+- POST /apps/<name>/render-route
+- POST /apps/<name>/deploy
+- POST /apps/<name>/stop
+- POST /apps/<name>/remove
+
+## Example payloads
+
+Create app:
+
+```json
+{
+  "name": "whoami",
+  "domain": "whoami.srazka.com",
+  "port": 18080,
+  "auth": true
+}
+```
+
+Remove and keep volumes:
+
+```json
+{
+  "keepVolumes": true
+}
+```
+
+## Local test
+
+```bash
+curl -s http://127.0.0.1:9911/health | jq .
+curl -s http://127.0.0.1:9911/apps | jq .
+```