Fix assets:create 404: form-urlencoded mot /apps/richdocuments/assets, intern CODE över HTTP

- lib/bridge.js createAssetLink: POST <nextcloudUrl>/apps/richdocuments/assets
  (utan index.php), Content-Type application/x-www-form-urlencoded med body
  path=<urlencoded>, path trimmad utan ledande slash (userFolder->get relativt
  filrot), OCS-APIRequest borttagen. Fel inkluderar statusCode + svarskropp.
- Intern collaboraUrl är HTTP: http://code:9980 (fallback http://<bridge-ip>:9980)
  i nc-collab-config default, .env.example, example-flows.json, docker-compose,
  install.sh och integrate-into-nodered.sh resolve_collabora_url.
- Publik WOPI-URL dokumenterad som https://docs.domain.name.
- package-lock.json för deterministisk form-data-install i Docker.

README.md

@@ -50,6 +50,11 @@ Palette: **nextcloud collabora** — six nodes in the same purple, all wired to
 
 `nc-collab-config` · `collabora-bridge` · `nc-office` · `collabora-convert` · `collabora-extract` · `collabora-transform` · `collabora-wopi`
 
+## Collabora URLs — intern vs publik
+
+- **Intern `collaboraUrl`** (Node-RED → CODE): plain **HTTP** — `http://code:9980` när CODE delar nätverk med Node-RED, eller fallback `http://<bridge-ip>:9980` (t.ex. `172.17.0.x`) efter `docker network connect bridge nextcloud-node-red`. Aldrig HTTPS mot bridge-IP.
+- **Publik `collaboraPublicUrl`** (browser/WOPI): `https://docs.domain.name` — CODE via reverse proxy.
+
 Full guide and examples: **[docs/NODES.md](docs/NODES.md)** · import **[flows/example-flows.json](flows/example-flows.json)**
 
 ## Install on any Nextcloud VM