feat(relay): rendezvous-relay service — 7 packages + plans (contracts/transport/agent/control-plane/e2e/auth/web)

Multi-tenant reverse-tunnel service ("ngrok for Claude Code" with E2E): a
host-agent dials OUT to an operator-run relay; external devices reach the host
THROUGH the relay, routed by per-tenant subdomain, forwarding ciphertext only
(the relay never sees plaintext). Lets a customer reach their own self-hosted
web-terminal from anywhere with zero networking setup.

Packages — all tsc-strict + vitest green (656 tests), cross-package integration verified:
- relay-contracts: frozen shared contracts (mux frame codec, data model,
  capability token, E2E envelope, pairing) — the src/types.ts analog
- term-relay:   native WS mux + stateless data plane (subdomain routing, ciphertext forward)
- agent:        host-agent (pairing, per-host Ed25519 + mTLS dial-out, forwards to 127.0.0.1:3000)
- control-plane: accounts/hosts registry, pairing-code flow, routing table, provisioning
- relay-e2e:    browser<->agent E2E (X25519 ECDH through relay, AEAD, anti-replay, recoverable replay key)
- relay-auth:   Passkey/WebAuthn, capability tokens, per-host certs, deny-by-default tenant isolation
- relay-web:    browser login + Web Crypto E2E + client-side preview rendering

Security invariants INV1-15 enforced; cross-tenant isolation CI tripwire live
(.github/workflows/relay-tripwire.yml). Design + implementation-level plans in
docs/PLAN_RELAY_*.md and docs/EXPLORE_RELAY_SERVICE.md.

NOTE: generated autonomously per the reviewed plans. The security-critical
packages (relay-e2e, relay-auth) REQUIRE expert security audit before any real
deployment — passing tests prove self-consistency, not resistance to attackers.
Base app (src/, public/) unchanged; concurrent desktop work left uncommitted.

relay-web/src/api-schemas.ts

@@ -0,0 +1,72 @@
+/**
+ * T2 — the frozen CLIENT-contract surface. Re-exports the `relay-contracts` §4.2/§4.3 shapes
+ * VERBATIM (never redefines them) and adds ONLY response envelopes needed to parse HTTP JSON.
+ *
+ * INV3: there is NO `account_id`/`tenant_id` REQUEST field anywhere here — identity is always the
+ * cookie/passkey session the browser already holds; the server derives the account.
+ *
+ * Wire note: over JSON, `HostRecord.agentPubkey` arrives base64url-encoded (a Uint8Array cannot
+ * ride JSON). The wire schema decodes it back to `Uint8Array` so callers receive a genuine
+ * `HostRecord` — validate-at-boundary (coding-style.md "Input Validation").
+ */
+import { z } from 'zod'
+import {
+  HostStatusSchema,
+  decodeBase64UrlBytes,
+  type HostRecord,
+  type HostStatus,
+  type CapabilityRight,
+} from 'relay-contracts'
+
+// Re-export the frozen types verbatim so P6 modules import them from one place (the src/types.ts
+// discipline: a new shared field is changed in relay-contracts, never redeclared locally).
+export type { HostRecord, HostStatus, CapabilityRight }
+export { HostStatusSchema }
+
+/** Wire form of a HostRecord: `agentPubkey` is base64url text, decoded to bytes on parse. */
+export const HostRecordWireSchema = z
+  .object({
+    hostId: z.string().uuid(),
+    accountId: z.string().uuid(),
+    subdomain: z.string().min(1),
+    agentPubkey: z.string().min(1),
+    enrollFpr: z.string().min(1),
+    status: HostStatusSchema,
+    lastSeen: z.string().min(1),
+    createdAt: z.string().min(1),
+    revokedAt: z.string().min(1).nullable(),
+  })
+  .strict()
+  .transform(
+    (w): HostRecord => ({
+      hostId: w.hostId,
+      accountId: w.accountId,
+      subdomain: w.subdomain,
+      // Copy into a fresh ArrayBuffer-backed Uint8Array so the type matches HostRecord exactly.
+      agentPubkey: new Uint8Array(decodeBase64UrlBytes(w.agentPubkey)),
+      enrollFpr: w.enrollFpr,
+      status: w.status,
+      lastSeen: w.lastSeen,
+      createdAt: w.createdAt,
+      revokedAt: w.revokedAt,
+    }),
+  )
+
+/** `GET /api/hosts` → array of HostRecord. */
+export const HostListWireSchema = z.array(HostRecordWireSchema).readonly()
+
+/** `GET /api/hosts/:id/status` → the host's current status. */
+export const HostStatusResponseSchema = z.object({ status: HostStatusSchema }).strict()
+
+/** `POST /api/pairing-codes` → single-use short-TTL code + its expiry (§4.5 ISSUE). */
+export const PairingCodeResponseSchema = z
+  .object({
+    code: z.string().min(1),
+    expiresAt: z.string().min(1),
+  })
+  .strict()
+  .readonly()
+export type PairingCodeResponse = z.infer<typeof PairingCodeResponseSchema>
+
+/** `POST /api/hosts/:id/capability-token` → opaque raw §4.3 token (v0.9+; never decoded to trust). */
+export const CapabilityTokenResponseSchema = z.object({ token: z.string().min(1) }).strict()