Add window-based variant placement strategy for Direct Probe Coordinates mode

Fix TypeError when fully_covered_bed_path is None

Support hg19 reference genome and PCR Amplicon sequencing style

Support variant generation in Direct BED Mode (ignoring MANE transcripts) and improve dynamic tracks in igv.js

Support loading MANE transcripts in igv.js, add toggles for CDS/intron/off-target variants, and add MANE transcripts download

Copy static files to both CWD static and script static paths to resolve 404

Add path diagnostics to Debug Info sidebar

Fix NameError by initializing uploaded_bed from session state before sidebar

Add sidebar debug info block

Fix IGV.js relative URLs and add layout/error handling

Add probe customization and random sampling features in streamlit UI

Add interactive IGV.js variant browser and static serving configuration