Related to #617
This fixes a misconfiguration scenario where Docker containers could
attempt direct SSH connections (producing [preauth] log spam) instead
of using the sensor proxy.
Changes:
- Fix container detection to check PULSE_DOCKER=true in addition to
system.InContainer() heuristics (both temperature.go and config_handlers.go)
- Upgrade temperature collection log from Error to Warn with actionable
guidance about mounting the proxy socket
- Add Info log when dev mode override is active so operators understand
the security posture
- Add troubleshooting section to docs for SSH [preauth] logs from containers
The container detection was inconsistent - monitor.go checked both flags
but temperature.go and config_handlers.go only checked InContainer().
Now all locations consistently check PULSE_DOCKER || InContainer().
dfe960deb4