[WIP] Fix Arduino compilation error in TankAlarm client

[Copilot]

Thanks for assigning this issue to me. I'm starting to work on it and will keep this PR's description up to date as I form a plan and make progress.

Original prompt

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This section details on the original issue you should resolve

<issue_title>Arduino Compilation Error in TankAlarm-092025-Client-Hologram (2025-11-11)</issue_title>
<issue_description>## Arduino Compilation Failed

The Arduino code compilation failed in the CI workflow.

Workflow Run: https://github.com/SenaxInc/ArduinoSMSTankAlarm/actions/runs/19280650809
Commit: 42367b2
Branch: master

Details

• Client Sketch: TankAlarm-092025-Client-Hologram/TankAlarm-092025-Client-Hologram.ino ❌
• Server Sketch: TankAlarm-092025-Server-Hologram/TankAlarm-092025-Server-Hologram.ino ✅
• Board: Arduino MKR NB 1500 (arduino:samd:mkrnb1500)
• Triggered by: push

Next Steps

1. Review the workflow logs for detailed error messages
2. Fix compilation errors in the Arduino code
3. Re-run the workflow to verify the fix

/cc @copilot</issue_description>

Comments on the Issue (you are @copilot in this section)

• Fixes Arduino Compilation Error in TankAlarm-092025-Client-Hologram (2025-11-11) #58

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