Trailer: what this show is

Show notes for the trailer. The audio is a synthetic placeholder—a slow pad rather than a voice—so the pipeline has something real to master before the first episode is written. scripts/podcast-encode.rs produced it: two-pass loudnorm to -16 LUFS and -1.5 dBTP, 128 kbps stereo, ID3v2.3 tags, chapters, and an embedded cover. It then ran ffprobe over the result and wrote the duration and byte count back into the frontmatter above, so the feed has everything it needs from content/ alone.

Note the show = "podcast" field: that's a typed @link(@Show) reference. If it pointed at a page that isn't a Show, the build would fail.