[client] Add stateful userspace firewall and remove egress filters

[lixmal]

Describe your changes

• Add stateful firewall functionality for UDP/TCP/ICMP in userspace firewalll
• Removes all egress drop rules/filters, still needs refactoring so we don't add output rules to any chains/filters.
• on Linux, if the OUTPUT policy is DROP then we don't do anything about it (no extra allow rules). This is up to the user, if they don't want anything leaving their machine they'll have to manage these rules explicitly.

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
8 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
2.5% Duplication on New Code

See analysis details on SonarQube Cloud

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