fix: address code review findings from 2026-08-17
- scope no-cache headers to non-static routes (restore immutable asset caching)
- reset cached rejected MongoDB promise so retries can succeed
- use last X-Forwarded-For entry in Content Editor rate limiter (anti-spoofing)
- remove weak Mongo defaults from compose files (fail loudly on missing env)
- move staging banner text to common.json content
- read APP_PORT from env file in deploy.sh healthcheck
- filter network noise from staging smoke console assertions
Closes MITHOME-48, MITHOME-49, MITHOME-50, MITHOME-51, MITHOME-52, MITHOME-53, MITHOME-54
Do Siki
bd7287aa58