[Alerts generator] Add Linux process events support for Visual Event Analyzer integration

[vgomez-el]

Current Issue
The alerts generated by the tool are not consistently showing the analyzer icon (cube icon) in Kibana's Alerts table. When the analyzer icon does appear and users click on it, they should see the visual event analyzer with the process tree, but this is not happening reliably for Linux-based alerts.

Current State - Working Example
Some Linux alerts already have the analyzer working correctly. Here's an example of what we want to achieve consistently:

Expected Behavior
All alerts generated from Linux hosts should include the necessary process events to make the Visual Event Analyzer available. Specifically:

• Alerts should have the analyzer icon visible in the Alerts table
• Clicking the analyzer icon should open the flyout with the analyzer graph already populated
• The process tree should show meaningful parent-child relationships for Linux processes

Technical Requirements
Based on Elastic's documentation, alerts need to include events with:

• agent.type: "endpoint" AND process.entity_id: *
• OR agent.type: "winlogbeat" AND event.module: "sysmon" AND process.entity_id: *

For Linux systems, we need to ensure alerts include:

• Process events with proper process.entity_id fields
• Parent-child process relationships (process.parent.* fields)
• Relevant event categories like process, file, network
• Timestamp sequences that create a logical timeline

Reference Alert Example
The "Binary Executed from Shared Memory Directory" alerts are already working correctly and can serve as a reference implementation. These alerts include proper process hierarchies like:
sh → python3.12 → sh → evil