chore(vendor): import pi 1.3.0

Imported as a linear vendor commit so forge rebases do not replay the upstream root tree.

git-subtree-dir: third_party/pi

git-subtree-split: 71023aec1546d6d677a65669c5665c0927ce0dd0

third_party/pi/packages/mcp/src/oauth/index.ts

@@ -0,0 +1,56 @@
+export {
+	type OAuthCallback,
+	type OAuthCallbackPage,
+	OAuthCallbackServer,
+	type OAuthCallbackServerOptions,
+} from "./callback.ts";
+export {
+	buildAuthorizationServerDiscoveryUrls,
+	discoverAuthorizationServerMetadata,
+	discoverOAuthServerInfo,
+	discoverProtectedResourceMetadata,
+	parseWwwAuthenticate,
+	resourceUrlFromServerUrl,
+	selectResource,
+} from "./discovery.ts";
+export {
+	McpOAuthAuthorizationRequiredError,
+	OAuthError,
+	OAuthInsecureEndpointError,
+	OAuthIssuerMismatchError,
+	OAuthRegistrationError,
+} from "./errors.ts";
+export {
+	type AddClientAuthentication,
+	adaptOAuthProvider,
+	authorizeMcp,
+	exchangeAuthorizationCode,
+	type OAuthClientMetadataDocument,
+	type OAuthClientProvider,
+	type OAuthFlowOptions,
+	type OAuthFlowResult,
+	refreshAuthorization,
+	registerClient,
+	startAuthorization,
+	stepUpScope,
+	type TokenRequestOptions,
+} from "./flow.ts";
+export {
+	McpOAuthProvider,
+	type McpOAuthProviderOptions,
+	type McpOAuthState,
+	type McpOAuthStateStore,
+	MemoryOAuthStateStore,
+} from "./provider.ts";
+export type {
+	AuthorizationServerMetadata,
+	OAuthChallenge,
+	OAuthClientInformation,
+	OAuthClientInformationFull,
+	OAuthClientInformationMixed,
+	OAuthClientMetadata,
+	OAuthDiscoveryState,
+	OAuthProtectedResourceMetadata,
+	OAuthServerInfo,
+	OAuthTokens,
+} from "./types.ts";