chore: clean up env templates, docs, and TODO

- .env.staging.default / .env.prod.default: remove dead Red/Green/Blue container
  vars, OSIT_WEB_PORT vars, DOCKER_AE_EXTRA_HOST entries, AE_APP_CFG_ID,
  AE_APP_NODE_PORT_RED/GREEN/BLUE, PUBLIC_AE_API_SERVER_INTERNAL; replace real
  staging key with XXXX placeholder (default files are committed to git);
  fix .prod PUBLIC_AE_API_PORT 5005 -> 443 (external rev proxy, not gunicorn)
- TODO__Agents.md: clean up completed items, condense history, update DevOps section
- PROJECT__AE_combined_front_back_Docker.md: mark unified Docker architecture complete

documentation/PROJECT__AE_combined_front_back_Docker.md

@@ -1,4 +1,7 @@
 # Project: Unified Aether Platform Orchestration (V3)
+> **Status: ✅ COMPLETE (2026-03-10)**
+> `ae_app` is live in `aether_container_env/docker-compose.yml`. Both frontend and backend deploy together via `npm run deploy:staging` / `npm run deploy:prod`. Internal `ae_api` networking active. Healthcheck wired. Old `ae_env_node_app` is superseded (archive when ready).
+
 > **Goal:** Consolidate the SvelteKit Frontend and FastAPI Backend into a single Docker Compose environment within `aether_container_env`.
 
 ## 1. Overview & Benefits