feat: propagate host UI theme into OnlyOffice loader (#16)

* Fix office theme persistence from host theme query

* fix: remove theme-system fallback

* fix: inherit theme query in editor iframe

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Co-authored-by: interpreterwork <interpreterwork@openinterpreter.com>
Co-authored-by: Victor A. <52110451+cs50victor@users.noreply.github.com>

Author: 3 people