fix: prevent malware manager lifecycle race (#926)

* fix: prevent malware manager lifecycle race

Signed-off-by: Khuswant Rajpurohit <khuswantrajpurohit18@gmail.com>

* fix: prevent malware manager lifecycle race

Signed-off-by: Khuswant Rajpurohit <khuswantrajpurohit18@gmail.com>

* fix: address lifecycle review feedback

Signed-off-by: Khuswant Rajpurohit <khuswantrajpurohit18@gmail.com>

* fix(malwaremanager): serialize ADD registration and bind scanner to cancellation lifecycle

Address review feedback for #917:
- Admit container registration under lock before executing pre-publication work
- Bind startMalwareManager to registration context and cancel backoff on removal
- Guard podToWlid and PID/shim publication against cancelled/superseded registrations
- Add deterministic regression tests for pre-publication interleaving and backoff cancellation

Signed-off-by: Khuswant Rajpurohit <khuswantrajpurohit18@gmail.com>

---------

Signed-off-by: Khuswant Rajpurohit <khuswantrajpurohit18@gmail.com>