refactor: remove /app frontend, consolidate on demo as sole UI

fix(demo): skip SVG bbox overlay in segmentation mode

feat: multi-object context and comparison system for chat panel

fix(demo): force card re-render on every backend sync

fix(demo): filter track cards, timeline, and logs to show only MATCH items

feat: wire explainability graph into inspection panel lifecycle

feat: add explainability state, API client, and HTML container

feat(inspection): quad view redesign — 2x2 simultaneous seg/edge/depth/3D

redesign: commercial-grade frontend for investor demo

fix: clean up video display — remove track ID labels, smaller fonts, masks-only for segmentation

feat(inspection): add inspection state sub-object

fix: use actual video FPS for frame index calculation to prevent track card disappearance

fix: keep last known tracks when backend returns empty frame data

fix: assessment flicker, pause/resume toggle, chat icons, overlay bbox scaling

refactor: replace canvas overlay with SVG-based bounding box system

feat(isr): frontend sends mission param, grays out non-relevant tracks, color-codes boxes

refactor: remove first-frame tab and simplify to video-only UI

refactor: remove remaining dead HEL/threat code remnants

refactor: strip threat fields from all frontend and backend code

refactor: delete dead threat code (threat_chat.py, hel.js)

feat: add timeline heatmap with detection highlights for Tab 2 video player

chore: remove dead code and unused frontend modules

fix: track cards update during playback + periodic GPT re-analysis

feat: click-to-select tracks on video overlay

feat(frontend): improve UI for detection and chat interaction

Rename UI terms: Reason->Detect, Engage->Track

Fix track cards stuck at UNASSESSED due to frontend race condition

Redesign track cards with inline features, remove separate features panel, clean up overlays

Update overlays, tracker, GPT reasoning, and threat chat improvements

feat: Add mission-driven object relevance abstractions

Show first frame radar when processed image appears

Add military-style radar with helicopter demo mode

Fix video playback race condition, local file protocol, and backend worker crash

feat: Implement depth-based distance estimation and frontend integration

feat: Real-time radar directionality via track sync

feat: Continuous object tracking, speed estimation, and overlay syncing

Refactor frontend into modular ES modules in frontend/ folder