The zap write path (zapSplit.js derivePointerTag) built the `a` coordinate
tag straight from `videoEvent.kind`. bitvid's internal video objects don't
always carry the Nostr kind — it can be 0 or undefined — and the inline
builder only rejected non-finite kinds, so a kind-0 object produced a
`0:pubkey:d` coordinate (Number.isFinite(0) === true). This flowed into both
the kind-9734 zap request and the kind-30081 bitvid tally.
The read side (zapTotals / mostZappedFeed) fetches totals by querying
`30078:pubkey:d` via buildVideoAddressPointer, which defaults invalid/zero
kinds to 30078. So the writer emitted `0:...` while the reader queried
`30078:...` — they never matched and every zap counted as zero, even after
a cache clear + refresh. Confirmed against live relays: 4 published bitvid
tallies all carried `0:...` coordinates while the real video events are
kind 30078.
Fix: derivePointerTag now delegates to the same canonical
buildVideoAddressPointer the reader uses, keeping writer and reader
coordinates in lockstep. Adds a regression test driving splitAndZap with
kind 0 / undefined / non-numeric video objects, asserting the zap request's
`a` tag defaults to `30078:pubkey:d`.
Co-Authored-By: Claude Opus 4.8 <[email protected]>
