fix: improve bpm reliability

fix: stop locking focus to keep iphone autofocus active

perf: 15s calibration window and weighted-median final bpm

perf: optimize signal processing pipeline and cleanup frontend

chore: setup deployment for Hugging Face with Docker and dynamic URLs

perf: optimize shader background rendering

fix: update final heart rate calculation to use only recent readings

feat: migrate rPPG pipeline to FaceLandmarker and 5-method adaptive extraction

fix: enforce minimum autocorrelation search range of 50 lags regardless of fps

fix: simplify status machine to calibrating timeframe, not signal quality gate

fix: reset bpm history on measuring entry and raise min bpm to 50

fix: move ROI from buggy forehead to cheeks with correct centering

fix: compute effective FPS from timespan to handle bursty WebSocket delivery

fix: improve BPM accuracy with first-peak autocorrelation and bandpass fix

feat: add measurement UI components and measure page with phase machine

feat: add webcam feed with face detection and RGB extraction

feat: redesign landing page with shader bg and animated CTA

feat: websocket endpoint, frontend utilities, face detection and pulse hook

feat: scaffold project