[System ready] Report ready status to Sysmonitor daemon

[fastiuk]

depends-on: sonic-net/sonic-buildimage#18817

Description

This change implements pmon's ability to report it's readines to sysmonitor

Motivation and Context

The motivation is to report the readiness of all SFPs to sysmonitor and not just the startup of pmon

How Has This Been Tested?

• Run NOS on the box
• Make sure pmon reports good readiness state and you can see it in sysmonitor

Additional Information (Optional)

[prgeor]

@fastiuk please update the details in the PR:-

Description
Motivation and Context
How Has This Been Tested?
Additional Information (Optional)`
``

[mihirpat1]

@fastiuk Can you please elaborate more on what do you mean by reporting the readiness of all SFPs?
Is readiness classified as

1. SfpStateUpdateTask has detected all SFPs present of the device?
2. CmisManagerTask has performed CMIS initialization of all CMIS SFPs?
3. XCVRD has spawned its child threads. In this case, readiness doesn't have any bearing on SFPs being detected or any child thread crashing while detecting or initializing the transceivers.

The above question is in reference to the below PR description
The motivation is to report the readiness of all SFPs to sysmonitor and not just the startup of pmon