fix: update activities count logic

[ulemons]

What

Updated the activity/query pipe to correctly handle the countOnly flag and to make the segments parameter robust when empty or undefined.

Why

Previously, the pipe always returned rows even when countOnly=1, leading to unnecessary data load.
Also, queries with empty segments could fail or return inconsistent results.

How

• Added conditional logic to return only count() when countOnly=1.
• Normalized segments to avoid errors when the parameter is empty or missing.
• Preserved all existing filters and G1–G5 logic.

[github-actions]

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