Remove watchdog tracking when backends stop, crash, or fail to start.
Validate eviction addresses under the model lifecycle lock so delayed
shutdowns cannot stop a replacement backend. Preserve replacement size
estimates when removing an old address.
Add lifecycle regression tests and document shutdown behavior.
Fixes#12331
Assisted-by: Codex:gpt-6
Co-authored-by: localai-org-maint-bot <306269227+localai-org-maint-bot@users.noreply.github.com>