Use events to deliver critical logs

[haouc]

Is your feature request related to a problem? Please describe.
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The controller's log is not exposed to customers since it runs in control plane. Instead of exposing it's logs to all customers' CW, the controller can also leverage events to share critical logs.
Describe the solution you'd like
A clear and concise description of what you want to happen.
The controller should use events to deliver important logs, such as

• pod IP/interface provisioning failure
• node interface provisioning failure
• IP starving in assigned subnet
• security group association events
  and more...
  Describe alternatives you've considered
  A clear and concise description of any alternative solutions or features you've considered.

Additional context
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[haouc]

We should add supports for this gradually. Adding them based on priority. It is ok to release supports in several versions.

[haouc]

The events for unsupported EC2 instance has been merged and will be released with v1.1.6 (#218 )