fix: master tcp reconnection issue

[alisitsyn]

Description

This PR fixes the issue of Modbus TCP Master to reestablish connection with the slave node as soon as possible. Current TCP Master supposed that all slaves should be available on starting connection phase and did not repair connection when connection error exists.

The above issue has been reproduced and confirmed as bug with IP101 Ethernet board. The port_tcp_master.c has been updated to repair connection cycle as soon as possible if the errors exist.

Related

Fixes EPROT-62 - #167

Testing

• The above issue has been reproduced and confirmed as bug. The port_tcp_master.c has been updated to repair connection cycle as soon as possible if the errors exist.
• Two scenarios have been checked during testing:

• TCP Slaves are not available during one minute after start then connected to the network.
• TCP Slaves are connected on start but become disconnected during more than 1 minute, then become alive again.
  In the above cases the TCP Master was able to establish connections as soon as possible and proceed with polling cycle correctly.

Checklist

• 🚨 This PR does not introduce breaking changes.
• All CI checks (GH Actions) pass.
• Documentation is updated as needed.
• Tests are updated or added as necessary.
• Code is well-commented, especially in complex areas.
• Git history is clean — commits are squashed to the minimum necessary.