lacma-2026 page: add 23s demo video (boot → notepat → waltz → fade)

Embed a looping demo video right after the masthead so reviewers see
the instrument in action immediately, above everything else. Captured
natively from AC Native hardware (not a screen recording of a browser):

- 0:00–0:05 Boot animation — "hi @jeffrey" rainbow text on cream
matrix-rain, no BIOS in between, runs straight from USB
- 0:05–0:22 notepat default piece playing a Viennese waltz. HUD
shows 32-voice synthesizer state: fx sliders, chord
color shifts tracking the played key, drum kit
labels (HAT-C, kick, snare), polyphonic voice meters
- 0:22–0:23 1-second fade-out

Stitched from /Desktop/ac-boot-shots/boot-jeffrey.mp4 +
demo-viennese.mkv via ffmpeg concat with 300ms fade-in and 1s fade-out.
Dual encoding: mp4 (h264/aac, 1.8 MB) primary, webm (vp9/opus, 2.8 MB)
fallback. JPG poster for the preload state.

New section markup uses a 1280:800 aspect-ratio frame with an
autoplay/muted/loop/playsinline video and a caption strip below the
frame: sequence chain ("boot → notepat → waltz → fade") on the left
and "bye @jeffrey ♡" in YWFT Processing on the right — the farewell
the user asked for, in the page rather than baked into the video.

Also updated the Video row in § Application at a Glance: no longer
says "filming tomorrow" — now points to the embedded player and
downloads, with word-count-style chip showing "under 5 min · ours: 23 s".

Assets:
ac-native-demo.mp4 1.8 MB
ac-native-demo.webm 2.8 MB
ac-native-demo-poster.jpg 25 KB

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>