Add userspace flow implementation

[lixmal]

Describe your changes

• Replace logger ringbuffer with channel (messages fall off at the end instead of at the beginning)
• Replace custom IPaddr with netip.Addr
• Replace net.IP allocations with netip.Addr
• Add inbound connection tracking
• Add userspace implementation for start/end flows

Issue ticket number and link

Checklist

• Is it a bug fix
• Is a typo/documentation fix
• Is a feature enhancement
• It is a refactor
• Created tests that fail without the change (if possible)
• Extended the README / documentation, if necessary

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
1 Accepted issue

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.9% Duplication on New Code

See analysis details on SonarQube Cloud