feat(teams): add createResendInvitationSender for the invitations seam

[vutuanlinh2k2]

What

Adds an opt-in shared helper createResendInvitationSender({ from, apiKey? }): SendInvitationEmailSeam behind a new subpath @tangle-network/agent-app/teams/resend, with resend as an optional peer.

Why

The teams invitations module exposes sendInvitationEmail as a per-app seam (so the core stays transport-agnostic). In practice every Resend-backed adopter hand-writes the same ~15-line wrapper — and both gtm-agent and creative-agent got it wrong the same way: resend.emails.send() returns { data, error } and does not throw on API-level failures (unverified domain, rate limit, bad recipient). A try/catch alone therefore records a failed send as emailStatus: 'sent'. Solving it once removes the silent-failure footgun fleet-wide.

How

src/teams/resend.ts — builds the client lazily (apiKey ?? RESEND_API_KEY; typed failure when neither is set), renders via the existing renderInvitationEmail(input, { fromAddress: from }), sends, and returns { succeeded: false, error } on both a thrown error and a non-null result.error, else { succeeded: true }.

sendInvitationEmail: createResendInvitationSender({ from: GTM_EMAIL_FROM })

resend is an optional peer, imported only in this subpath (same pattern as drizzle-orm/react/konva): apps not on Resend keep passing a raw seam, and the core never pulls a mail dependency. Invite-URL origin + from-address stay app-side (they're already injected params).

Verification

• New unit test (mock resend): no-key, success, result.error, and thrown-error paths.
• pnpm vitest run tests/teams — 86 passed. pnpm typecheck — 0 errors. pnpm build emits dist/teams/resend.{js,d.ts}.

Follow-ups (separate, in each app, after publish)

gtm-agent + creative-agent adopt createResendInvitationSender and delete their hand-rolled senders (which fixes creative's identical latent bug).

[tangletools]

✅ Auto-approved PR — fe20e359

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_{tangletools · auto-approval · reason: blanket_auto_approve · 2026-06-25T04:14:23Z}