v0.5.1

Hardware-accelerated exports plus a wave of quality-of-life features
inspired by the Sentry Studio feature set.

Highlights

• Hardware-accelerated export — exports now use GPU encoding when a
  working encoder is available (Apple VideoToolbox, NVIDIA NVENC, Intel
  QuickSync, VAAPI — probed once at startup with a real test encode, not
  just listed capabilities). Decode uses -hwaccel auto the same way. If
  a hardware encode fails mid-export, the export automatically retries
  once on CPU. EXPORT_HWACCEL=off restores the exact previous
  software-only pipeline. VAAPI/QuickSync need --device /dev/dri;
  NVENC needs --gpus all — see the README.
• Time & date format settings — TIME_FORMAT (12h/24h) and
  DATE_FORMAT (four layouts) drive every clock in the UI and the
  timestamp burned into exports, so the video always matches the screen.
• Event-trigger camera highlight — the camera that fired the event
  gets an amber dot in its tile label, so you look at the right footage
  first. Exports carry the same mark: a round amber dot inside the
  label chip of the trigger camera.
• Export overlays match the UI — camera labels in exports are now
  the same dark chips the player shows, drawn inside the footage
  instead of on the letterbox bars.
• Faster review — playback speeds now go up to 4x.
• Glass chrome — the app bar, drawer and control bar get a
  frosted-glass blur (UI_BLUR_PX, 0 disables it entirely).
• Update notification — the app checks GitHub for a newer release at
  most once per day and shows a badge on the version number linking to
  the release. UPDATE_CHECK=false disables the outbound call
  completely.

Fixes

• Camera labels stay inside the video frame when a tile letterboxes,
  instead of floating over the black bars, and no longer flash scaled
  text during the fullscreen animation.
• Event-list rows keep a visible gap between hover/active highlights.
• The telemetry HUD's speed block no longer touches the video content
  below the HUD strip.

Compatibility

No migration required. All new settings default to the previous behavior
or a gentle extension of it; EXPORT_HWACCEL=off reproduces the previous
export pipeline byte for byte. Air-gapped setups: the update check fails
silently and never surfaces an error. Portable builds that use a
system-installed ffmpeg now need ffmpeg 6.1 or newer (the export label
chips use per-side box borders).