fix(invites): call the real invite redemption endpoint in username claims

[mbradley]

Bug

src/routes/username.ts:320 calls POST ${INVITE_FAUCET_URL}/api/invite/redeem. That endpoint does not exist on the invite-darshan service.

divine-invite-darshan exposes /v1/consume-invite (and related) under the /v1/ prefix; the /api/invite/redeem path returns 404 from the faucet's route table.

Impact

Any username-claim flow that requires an invite redemption will fail silently (the code/path treats redemption as a precondition to reservation). If INVITE_FAUCET_URL is set in the environment, the redemption call 404s; if it's unset, the branch is skipped. Either way, the redemption side of the flow doesn't happen, and name-server reservations that should be invite-gated are effectively ungated.

Recommended fix

Update the URL to call the real endpoint (${INVITE_FAUCET_URL}/v1/consume-invite) and adjust the request body / auth to match that endpoint's contract. That endpoint requires a NIP-98 auth header signed by the invitee's keypair — if the name-server doesn't have access to the invitee's signer, this redemption path needs an alternative (e.g., a dedicated admin-level endpoint on invite-darshan that consumes a code on behalf of a target pubkey, which would itself be a new feature on invite-darshan).

Alternatively, remove the redemption branch if it's vestigial.

Origin

Identified during ecosystem audit for divine-invite-darshan PR #39. Flagged because it lives in the invite-code redemption path and silently no-ops today.

[DSanich]

@mbradley @NotThatKindOfDrLiz I checked the name-server side, and I don’t think this can be fixed with just a URL change.

The current /api/username/reserve flow only has name, email, and invite_code. It doesn’t have the invitee’s pubkey or a NIP-98 signature for the invite service request, so name-server can’t call /v1/consume-invite correctly on behalf of the user.

I think we have two realistic options:

1. Add a server/admin endpoint in invite-darshan that name-server can call with the code + target identity.
2. Move invite redemption to the client, where the user can actually sign the NIP-98 request.

If the invite path is no longer intended, we should probably remove it from name-server so it doesn’t look like invite-gating is working when it isn’t.