fix: Reject CTID network IDs above 16 bits

[GautamBytes]

Summary

• Preserve the full 32-bit ETL network ID until CTID range validation, so IDs above 65535 cannot be truncated into misleading CTIDs.
• Keep expanded transaction JSON on the same 32-bit path.
• Add focused encoder and tx handler regression tests.

Fix #3158

[mathbunnyru]

@GautamBytes could you please sign your commit?

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[GautamBytes]

@GautamBytes could you please sign your commit?

DONE