added sample both local docker and system ngins options

docs/architecture/05-sidebar-injection.md

@@ -57,9 +57,52 @@ Next.js and other streaming SSR frameworks may not include `</body>` in the init
 
 ## Nginx Configuration
 
-### For Local Development (system nginx)
+There are two options for local development:
 
-Each room needs entries in `/etc/nginx/sites-enabled/`:
+### Option 1: Docker Nginx (Recommended for portability)
+
+Each room includes a docker-compose.nginx.yml that runs nginx in a container.
+
+```bash
+# Add to /etc/hosts
+127.0.0.1 sample.spr.local.ar sample.local.ar
+
+# Start room with nginx
+cd gen/<room>/soleprint
+docker compose -f docker-compose.yml -f docker-compose.nginx.yml up -d
+```
+
+The nginx config in `cfg/<room>/soleprint/nginx/local.conf` uses docker service names:
+
+```nginx
+location /spr/ {
+    proxy_pass http://soleprint:8000/;
+}
+
+location / {
+    proxy_pass http://frontend:80;
+    # ... sub_filter for sidebar injection
+}
+```
+
+**Pros**: Portable, no system dependencies, isolated per room
+**Cons**: Only one room can use port 80 at a time
+
+### Option 2: System Nginx (For running multiple rooms)
+
+If you need multiple rooms running simultaneously, use your system's nginx.
+
+1. Install nginx: `sudo apt install nginx`
+
+2. Add hosts entries for all rooms:
+```
+# /etc/hosts
+127.0.0.1 amar.spr.local.ar amar.local.ar
+127.0.0.1 dlt.spr.local.ar dlt.local.ar
+127.0.0.1 sample.spr.local.ar sample.local.ar
+```
+
+3. Create config in `/etc/nginx/sites-enabled/spr_local.conf`:
 
 ```nginx
 # room.spr.local.ar - app with sidebar
@@ -79,7 +122,10 @@ server {
     # Backend API (if applicable)
     location /api/ {
         proxy_pass http://127.0.0.1:BACKEND_PORT/api/;
-        # ... headers
+        proxy_set_header Host $host;
+        proxy_set_header X-Real-IP $remote_addr;
+        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
+        proxy_set_header X-Forwarded-Proto $scheme;
     }
 
     # Frontend with sidebar injection
@@ -102,24 +148,14 @@ server {
 server {
     listen 80;
     server_name room.local.ar;
-    # ... same as above but without sub_filter
+    # ... same locations but without sub_filter in / block
 }
 ```
 
-### For Docker/AWS (nginx container)
+4. Reload nginx: `sudo nginx -t && sudo systemctl reload nginx`
 
-The nginx config lives in `cfg/<room>/soleprint/nginx/local.conf` and uses docker service names instead of localhost ports:
-
-```nginx
-location /spr/ {
-    proxy_pass http://soleprint:8000/spr/;
-}
-
-location / {
-    proxy_pass http://frontend:3000;
-    # ... sub_filter same as above
-}
-```
+**Pros**: Multiple rooms on port 80 via different hostnames
+**Cons**: Requires system nginx, manual config updates
 
 ## Port Allocation