File creation agent skills (#5280)

* Powerpoint File Creation (#5278)

* wip

* download card

* UI for downloading

* move to fs system with endpoint to pull files

* refactor UI

* final-pass

* remove save-file-browser skill and refactor

* remove fileDownload event

* reset

* reset file

* reset timeout

* persist toggle

* Txt creation (#5279)

* wip

* download card

* UI for downloading

* move to fs system with endpoint to pull files

* refactor UI

* final-pass

* remove save-file-browser skill and refactor

* remove fileDownload event

* reset

* reset file

* reset timeout

* wip

* persist toggle

* add arbitrary text creation file

* Add PDF document generation with markdown formatting (#5283)

add support for branding in bottom right corner
refactor core utils and frontend rendering

* Xlsx document creation (#5284)

add Excel doc & sheet creation

* Basic docx creation (#5285)

* Basic docx creation

* add test theme support + styling and title pages

* simplify skill selection

* handle TG attachments

* send documents over tg

* lazy import

* pin deps

* fix lock

* i18n for file creation (#5286)

i18n for file-creation
connect #5280

* theme overhaul

* Add PPTX subagent for better results

* forgot files

* Add PPTX subagent for better results (#5287)

* Add PPTX subagent for better results

* forgot files

* make sub-agent use proper tool calling if it can and better UI hints