Fix set_page_config: page_layout -> layout (emoji-strip regression)

Remove all emoji from code, docs, and navigation

Navigation router (branding + Demo View + collapsible Build hierarchy); full-range LoD slider (1-9, default 7); replace deprecated use_container_width

Sync demo (downloads, build summary, HCP depth fix) + latest approach_1; clean canonical outputs

Add multipage deployment: demo viewer + Baseline/Approach 1/Approach 2 pages + pre-built outputs + HF Space config