Fix network boot issues and add power management configuration

- Resolve SSH lockout after reboot caused by systemd lid switch suspend
- Add systemd-logind configuration to disable lid switch handling
- Add NetworkManager configuration for static IP and power management
- Update network troubleshooting documentation with complete solution
- Include diagnostic commands and deployment steps

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

config/systemd/01-server-logind.conf

@@ -0,0 +1,14 @@
+# systemd logind configuration for headless server operation
+# Deploy: sudo cp config/systemd/01-server-logind.conf /etc/systemd/logind.conf.d/
+
+[Login]
+# Disable all power management triggers for headless server
+HandleLidSwitch=ignore
+HandleLidSwitchExternalPower=ignore
+HandleLidSwitchDocked=ignore
+
+# Prevent automatic suspend/hibernate
+IdleAction=ignore
+
+# Keep the system running even when no users are logged in
+KillUserProcesses=no