fix: container orchestration stability, AIUI inclusion, lnd-ui port, version 1.3.0

Container stability:
- Merge scan results instead of full replacement (prevents UI flapping)
- Absence threshold: 3 consecutive missed scans before removing from state
- container-list RPC uses cached scanner state for consistency
- Increased Podman API timeout 30s → 60s (scanner + health monitor)
- Keep crashed containers visible as "exited" instead of podman rm -f
- Resolve host-gateway IP via ip route (podman 4.3.x compatibility)

ISO build fixes:
- AIUI web app inclusion: searches 5 paths + CI step to copy from build server
- Claude API proxy: systemctl enable with symlink fallback
- AIUI nginx: try_files =404 (was /aiui/index.html redirect loop)
- Build version set to 1.3.0

Container fixes:
- lnd-ui: nginx listens on 8080 (was 80, Permission denied in rootless)
- first-boot: image-versions.sh sourced from correct path with validation
- first-boot: host-gateway resolved to actual gateway IP

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

docker/lnd-ui/Dockerfile

@@ -17,6 +17,6 @@ COPY bg-intro.jpg /usr/share/nginx/html/assets/img/
 # Copy nginx config
 COPY nginx.conf /etc/nginx/conf.d/default.conf
 
-EXPOSE 80
+EXPOSE 8080
 
 CMD ["nginx", "-g", "daemon off;"]

docker/lnd-ui/nginx.conf

@@ -1,5 +1,5 @@
 server {
-    listen 80;
+    listen 8080;
     server_name _;
 
     root /usr/share/nginx/html;