Add node docs, collabora purple UI, and portable install env

Human-readable help in all six palette nodes, docs/NODES.md with usage examples, expanded example flows, and auto-detect NODERED_DIR plus CODE bridge IP from .env on any VM.

nodes/collabora-wopi.html

@@ -1,7 +1,7 @@
 <script type="text/javascript">
     RED.nodes.registerType('collabora-wopi', {
         category: 'nextcloud collabora',
-        color: '#0082c9',
+        color: '#7950a2',
         defaults: {
             name: { value: '' },
             config: { type: 'nc-collab-config', required: true },
@@ -38,6 +38,27 @@
 </script>
 
 <script type="text/html" data-help-name="collabora-wopi">
-    <p>WOPI discovery/capabilities och editor-URL. Agenten ska nästan aldrig PutFile — använd WebDAV PUT.</p>
-    <p><code>buildEditor</code>: <code>msg.wopiSrc</code> + <code>msg.token</code> → <code>msg.editorUrl</code>.</p>
+    <p>Inte filkonvertering — hälsokoll och WOPI-hjälp mot CODE.</p>
+
+    <table style="width:100%; font-size:12px;">
+        <tr><th>Operation</th><th>Du får</th></tr>
+        <tr><td><code>capabilities</code></td><td>JSON: vad CODE kan (convert-to m.m.)</td></tr>
+        <tr><td><code>discovery</code></td><td>XML: mime → editor-URL</td></tr>
+        <tr><td><code>buildEditor</code></td><td><code>msg.editorUrl</code> från <code>msg.wopiSrc</code> + <code>msg.token</code></td></tr>
+        <tr><td><code>checkFileInfo</code></td><td>JSON om filen (WOPI-host, oftast Nextcloud)</td></tr>
+        <tr><td><code>getFile</code></td><td>filbytes via WOPI GET</td></tr>
+    </table>
+
+    <p><code>buildEditor</code> sätter ungefär:<br>
+    <code>{collaboraPublicUrl}/browser/dist/cool.html?WOPISrc=...&amp;access_token=...</code><br>
+    Publik URL = Nextcloud/proxy (<code>https://cloud.hannesahlin.se</code>), inte intern CODE-IP.</p>
+
+    <h4>När</h4>
+    <ul>
+        <li>Första test att CODE lever → <code>capabilities</code></li>
+        <li>WOPI-token från <code>nc-office document:direct</code> → bygg iframe-URL</li>
+        <li>Felsökning. Spara filer via WebDAV, inte WOPI PutFile.</li>
+    </ul>
+
+    <pre>inject → collabora-wopi (capabilities) → debug</pre>
 </script>