* add implementation plan
* website: remove unnecessary libsodium direct dependency from file page plan
* website: update file page plan for async encryption, tailwind, no worker
* add product plan
* update product plan based on the feedback
* remove implementation details from product plan
* update product plan
* add updated implementation plan
* website: add build infrastructure for /file route
* website: fix card click and overlay hash handling for /file page
* website: add /file page with XFTP file transfer and protocol overlay
* website: redesign /file page layout and styling
* fix(website): scope hero h1/h2 font overrides to .hero-section-1
* fix(website): fix /file overlay diagram scaling on short viewports
* style(website): match /file page top padding with /directory
* website: remove file page in navbar
* website: switch xftp-web to official one
* website: fix web.sh
* update texts
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Co-authored-by: Evgeny Poberezkin <evgeny@poberezkin.com>
