Clearing "Full Name" in the profile settings shows success but keeps the
old value: since #31959 it is only updated when non-empty, because the
input is disabled (not submitted) when `change_full_name` is disabled.
Use `*string` for the field, so a missing field keeps the value and an
empty one clears it. With `change_full_name` disabled, any submitted
value (including empty) is now rejected. Not `optional.Option[string]`,
because `MaxSize` would count slice elements instead of characters.
Fixes#40185
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AI disclosure: written with Claude Code (claude-opus-5-5) and tested
locally.
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Co-authored-by: Claude Opus 5.5 <noreply@anthropic.com>
Co-authored-by: wxiaoguang <wxiaoguang@gmail.com>
Co-authored-by: silverwind <me@silverwind.io>
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