feat(alerts): add Flowtriq alert module for DDoS correlation

[jacob-masse]

Summary

• Adds alert_flowtriq.sh module that POSTs server alerts (crashes, restarts, monitor failures, updates) to a configurable Flowtriq webhook endpoint
• Adds dispatch logic in alert.sh following the same pattern as existing alert providers
• Adds flowtriqalert and flowtriqwebhook config entries to all 139 default server configs

Why

Game servers are frequent DDoS targets. When LinuxGSM detects a server crash, restart, or monitor failure, this module sends the event to Flowtriq's webhook API so operators can correlate server issues with DDoS attacks detected on their network. This helps distinguish between application-level problems and network-layer attacks, reducing mean time to resolution.

Config

# Flowtriq Alerts | https://docs.linuxgsm.com/alerts/flowtriq
flowtriqalert="off"
flowtriqwebhook="webhook"

Test plan

• Enable flowtriqalert="on" and set flowtriqwebhook to a valid endpoint
• Run ./gameserver test-alert and verify the JSON payload is received
• Verify ShellCheck passes on alert_flowtriq.sh
• Verify test-alert prints appropriate warnings when Flowtriq is not configured