`log_level` metadata is not accurate

[Jen Huang]

Follow up to the discussion in elastic/kibana#180778

Reproduction:

1. Enroll a new agent into a policy that already has log level set to debug
2. Observe that the agent successfully sent debug logs
3. View agent document, observe that local_metadata.elastic.agent.log_level is reporting info even though it is running at debug level from its policy

[Elastic Machine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[Nicolas Chaulet]

FYI where it's used in kibana

[Jen Huang]

FYI where it's used in kibana

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