fix: replace generic exit 1 with specific exit codes in ct/ and install/ scripts (#12475)

Part of #12467 — scripts only (no framework changes).

New exit codes 250-254 registered in api.func and error_handler.func:
- 250: App download failed or version not determined
- 251: App file extraction failed (corrupt/incomplete archive)
- 252: App required file or resource not found
- 253: App data migration required — update aborted
- 254: App user declined prompt or input timed out

Existing codes reused where applicable:
- 10: privileged/Docker required (unifi-os-server)
- 64: invalid user input (postgresql, tomcat)
- 71: system error (pulse useradd)
- 150: service failed to start (docker, npmplus)
- 153: build failed (booklore)
- 233: app not installed (evcc, endurain, grafana, loki, itsm-ng)
- 236: hardware not detected (unifi-os-server /dev/net/tun)
- 238: OS not supported (frigate)

install/npmplus-install.sh

@@ -51,7 +51,7 @@ while true; do
   attempts=$((attempts + 1))
   if [[ "$attempts" -ge 3 ]]; then
     msg_error "Maximum attempts reached. Exiting."
-    exit 1
+    exit 254
   fi
 done
 
@@ -76,11 +76,11 @@ for i in {1..60}; do
     elif [[ "$STATUS" == "unhealthy" ]]; then
       msg_error "NPMplus container is unhealthy! Check logs."
       docker logs "$CONTAINER_ID"
-      exit 1
+      exit 150
     fi
   fi
   sleep 2
-  [[ $i -eq 60 ]] && msg_error "NPMplus container did not become healthy within 120s." && docker logs "$CONTAINER_ID" && exit 1
+  [[ $i -eq 60 ]] && msg_error "NPMplus container did not become healthy within 120s." && docker logs "$CONTAINER_ID" && exit 150
 done
 msg_ok "Builded and started NPMplus"