feat(sdk): Effect v4 + @effect/openapi-generator; typed pf.api & example ladder

Drop Orval for the first-party @effect/openapi-generator (OpenAPI 3.1 ->
Effect Schema + a typed HttpClient client) and bump effect 3.19 ->
4.0.0-beta.98. Port the hand-written surfaces to the v4 API (Result over
Either, Context.Service, Codec, Literals/Union arrays, Stream/Schedule/
Effect renames). Transport (CA-pinning fetch) and the reconnecting SSE
source are kept intact.

Make the SDK approachable for non-Effect users:
- Add pf.api.* on the Promise facade: the generated client surfaced as
  typed, Promise-native methods (await pf.api.listPairedClients()), so REST
  calls are autocompleted and checked instead of stringly-typed
  pf.request(method, path, body) + `as` casts. Zero-drift veneer over
  make(httpClient), backed by the same pinning fetch. pf.request stays as
  the untyped escape hatch.
- Re-tier examples into a 1-4 complexity ladder, rewritten onto pf.api.*
  (the typed payloads caught a wrong `launch` shape in provider-sync);
  the Effect example is labelled advanced. Add examples/ to tsconfig so
  they are typechecked (stops rot).

typecheck + 19 tests green.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

sdk/examples/notify-pairing.ts

@@ -1,5 +1,7 @@
-// The flagship hook-with-a-decision pattern (Promise facade): watch pairing requests, notify,
-// and approve/deny THROUGH the API — asynchronously, the punktfunk way (hooks never veto).
+// ── Example 2/4 · event → decision ──────────────────────────────────────────────────────────
+// The flagship pattern: watch pairing requests, notify yourself, and approve/deny THROUGH the
+// typed API — asynchronously, the punktfunk way (hooks never veto). Every call is checked and
+// autocompleted; no hand-written paths, no casts.
 import { connect } from "../src/index.js";
 
 const pf = await connect();
@@ -7,9 +9,13 @@ console.log("watching for pairing requests…");
 
 pf.events.on("pairing.pending", async (e) => {
 	console.log(`pairing request: ${e.device.name} (${e.device.fingerprint})`);
-	// Wire your real notifier here (ntfy, Pushover, Home Assistant, …), then decide:
-	//   const pending = await pf.request("GET", "/native/pending") as { id: number }[];
-	//   await pf.request("POST", `/native/pending/${pending[0].id}/approve`);
+
+	// Wire your real notifier here (ntfy, Pushover, Home Assistant, …). Then decide by calling
+	// the API — find the pending device by fingerprint and approve it (send `{}` to keep the
+	// name it knocked with):
+	const pending = await pf.api.listPendingDevices();
+	const match = pending.find((d) => d.fingerprint === e.device.fingerprint);
+	if (match) await pf.api.approvePendingDevice(String(match.id), { payload: {} });
 });
 pf.events.on("pairing.completed", (e) => console.log(`paired: ${e.device.name}`));
 pf.events.on("pairing.denied", (e) => console.log(`denied: ${e.device.name}`));