Fix install-guide bind-mount ownership to the real container UID (#210)

The guide told users to chown 1000:1000, but the image runs as 1654:1654
(APP_UID) — the exact confusion reported in #210. README was already
corrected; this aligns the served install guide with it.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Shared.Rcl/wwwroot/raw_docs/install-guide.md

@@ -92,16 +92,16 @@ If you see:
 Access to the path '/app/config/config.yaml' is denied.
 ```
 
-Fix ownership:
+Fix ownership — RackPeek runs as UID/GID **1654:1654** inside the container:
 
 ```bash
-sudo chown -R 1000:1000 /path/on/host/rackpeek
+sudo chown -R 1654:1654 /path/on/host/rackpeek
 ```
 
-Or explicitly set the container user:
+You can verify the container user with:
 
-```yaml
-user: "1000:1000"
+```bash
+docker exec rackpeek id
 ```
 
 RackPeek must be able to: