Add missing configuration options for agent monitoring (standalone agent)

[kilfoyle]

The page Configure monitoring for standalone Elastic Agents is missing a couple of settings.

• agent.monitoring.diagnostics.limit.interval
• agent.monitoring.diagnostics.limit.burst
• agent.monitoring.diagnostics.uploader.max_retries
• agent.monitoring.diagnostics.uploader.max_dur

Rel: #1361
Rel: #1333

See elastic-agent.reference.yaml for details.

# agent.monitoring:
#   # enabled turns on monitoring of running processes
#   enabled: false
#   # enables log monitoring
#   logs: false
#   # enables metrics monitoring
#   metrics: false
#   # metrics_period defines how frequent we should sample monitoring metrics. Default is 60 seconds.
#   metrics_period: 60s
#   # exposes /debug/pprof/ endpoints
#   # recommended that these endpoints are only enabled if the monitoring endpoint is set to localhost
#   pprof.enabled: false
#   # The name of the output to use for monitoring data.
#   use_output: monitoring
#   # Exposes agent metrics using http, by default sockets and named pipes are used.
#   #
#   # `http` Also exposes a /liveness endpoint that will return an HTTP code depending on agent status:
#   # 200: Agent is healthy
#   # 500: A component or unit is in a failed state
#   # 503: The agent coordinator is unresponsive
#   #
#   # You can pass a `failon` parameter to the /liveness endpoint to determine what component state will result in a 500.
#   # For example: `curl 'localhost:6792/liveness?failon=degraded'` will return 500 if a component is in a degraded state.
#   # The possible values for `failon` are:
#   # `degraded`: return an error if a component is in a degraded state or failed state, or if the agent coordinator is unresponsive.
#   # `failed`: return an error if a unit is in a failed state, or if the agent coordinator is unresponsive.
#   # `heartbeat`: return an error only if the agent coordinator is unresponsive.
#   # If no `failon` parameter is provided, the default behavior is `failon=heartbeat`
#   http:
#       # enables http endpoint
#       enabled: false
#       # The HTTP endpoint will bind to this hostname, IP address, unix socket or named pipe.
#       # When using IP addresses, it is recommended to only use localhost.
#       host: localhost
#       # Port on which the HTTP endpoint will bind. Default is 0 meaning feature is disabled.
#       port: 6791
#       # Metrics buffer endpoint
#       buffer.enabled: false
#   # Configuration for the diagnostics action handler
#   diagnostics:
#       # Rate limit for the action handler. Does not affect diagnostics collected through the CLI.
#       limit:
#           # Rate limit interval.
#           interval: 1m
#           # Rate limit burst.
#           burst: 1
#       # Configuration for the file-upload client. Client may retry failed requests with an exponential backoff.
#       uploader:
#           # Max retries allowed when uploading a chunk.
#           max_retries: 10
#           # Initial duration of the backoff.
#           init_dur: 1s
#           # Max duration of the backoff.
#           max_dur: 1m

[kilfoyle]

It turns out that these settings affect only Fleet-managed Elastic Agent, so they shouldn't be documented on the standalone agents page. Closing...