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.

lib/bridge.js

@@ -2,6 +2,7 @@
 
 const { webdavGet, webdavPut, webdavPropfindFileId } = require('./webdav');
 const { ocsRequest } = require('./ocs');
+const { requestBuffer } = require('./http-client');
 const { convertTo, extractStructure, transformStructure } = require('./collabora');
 const {
     resolveDestNcPath,
@@ -210,33 +211,46 @@ async function extractToPayload(config, msg) {
 }
 
 async function createAssetLink(config, msg) {
-    const assetPath = pickMsgField(msg, 'ncPath');
+    const assetPath = pickMsgField(msg, 'ncPath', 'path');
     if (!assetPath) {
-        throw new Error('createAssetLink kräver msg.ncPath');
+        throw new Error('createAssetLink kräver msg.ncPath eller msg.path');
     }
 
-    const relPath = normalizeNcPath(assetPath);
-    const { requestBuffer } = require('./http-client');
-    const base = config.nextcloudUrl.replace(/\/$/, '');
+    // richdocuments AssetsController::create($path) läser form-parametern 'path'
+    // och slår upp filen relativt användarens filrot → ingen ledande slash.
+    const relPath = String(assetPath).trim().replace(/^\/+/, '').replace(/\/{2,}/g, '/');
+    const base = String(config.nextcloudUrl || '').replace(/\/+$/, '');
     const token = Buffer.from(`${config.username}:${config.password}`).toString('base64');
+
     const res = await requestBuffer({
-        url: `${base}/index.php/apps/richdocuments/assets`,
+        url: `${base}/apps/richdocuments/assets`,
         method: 'POST',
         headers: {
             Authorization: `Basic ${token}`,
-            'OCS-APIRequest': 'true',
-            'Content-Type': 'application/json',
-            Accept: 'application/json'
+            Accept: 'application/json',
+            'Content-Type': 'application/x-www-form-urlencoded'
         },
-        body: Buffer.from(JSON.stringify({ path: relPath }), 'utf8'),
+        body: Buffer.from(`path=${encodeURIComponent(relPath)}`, 'utf8'),
         rejectUnauthorized: config.verifyTls !== false && config.verifyTls !== 'false'
     });
 
+    const bodyText = res.body.toString('utf8').trim();
+
     if (res.statusCode < 200 || res.statusCode >= 300) {
-        throw new Error(`assets:create misslyckades (${res.statusCode})`);
+        throw new Error(
+            `assets:create misslyckades (${res.statusCode}): ${bodyText || '<tom body>'} — ` +
+            `path=${relPath}, url=${base}/apps/richdocuments/assets. ` +
+            '404 = filen saknas i användarens rot eller fel nextcloudUrl.'
+        );
+    }
+
+    let json;
+    try {
+        json = JSON.parse(bodyText);
+    } catch (e) {
+        throw new Error(`assets:create: ogiltigt JSON-svar (${res.statusCode}): ${bodyText.slice(0, 200)}`);
     }
 
-    const json = JSON.parse(res.body.toString('utf8'));
     return {
         assetUrl: json.url || json.assetUrl || json,
         ncPath: relPath