Delete assets/architecture.svg

Upload pdfi-uml.svg

chore(assets): remove deprecated PNG favicon

docs: add static architecture diagram (architekture.svg) for fallback rendering

replace blurry PNG favicon with crisp SVG vector graphic for optimal scaling

add: favicon, modified pdfi-avatar.svg

style: remove copyright text from avatar svg for cleaner chat UI

feat: integrate custom PDF'i SVG avatar into UI