The site hardcodes platform URLs across 7+ components; this consolidates them into
one typed source. models.py: Platform/LinkKind/ReleaseKind enums + PresenceLink,
ReleaseTrack, Release, Presence. presence.authored.yaml = verified inventory (6
profiles, 4 releases, 18 links) with provenance; build_presence.py validates →
presence.json and stamps default file-provenance. Wired into tide.py build +
generated TS (Presence interface) so the site can later consume it — one-directional,
opt-in (site keeps owning editorial gig content). Per-track links modelled as a
capability, populated only where a real direct URL exists. 61 tests green.
