display_name maxLength is too small, should be 256 characters

[stephdl]

Steps to reproduce

• Open ns8-samba module in NethServer UI
• Try to set a display name with more than 32 characters for a user
• Save settings

Expected behavior

The display name input should accept up to 256 characters, matching the expected maximum for names in some environments or integration scenarios.

Actual behavior

The display name field was limited to 32 characters, so longer names could not be set.
Users with longer display names could not be properly managed or created.

Components

ns8-samba
NethServer UI
validate-input.json

See also

Related PR: NethServer/ns8-samba#204

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