RTECO-1368 - Fix metrics collection for agent detection and interactive context fields

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RTECO-1368: Fix dropped agent metric labels (is_agent, agent, is_interactive)

Problem

PR #1555 (RTECO-1017) added agent/CI context fields to MetricsData and
populated them in metrics_collector.go, but the labels were silently dropped
on the way to the visibility wire payload. Prod logs (jfcli_commands_count)
still don't show is_agent, agent, or is_interactive.

Root cause

Two broken links in the chain:

1. commandsCountLabels struct in commands_count_metric.go had no fields
   for the new agent labels, so they could never be serialized.
2. reportUsageToVisibilitySystem in command.go didn't copy the new
   fields from collected MetricsData into visibility.MetricsData.

Depends on:

1. core - RTECO-1368 - Fix metrics collection for agent detection and interactive context fields jfrog-cli-core#1566