HTTP transport for call/publish (#1512)

- New `HttpTransport` (lib/runtime/transports/http.js): POST /{basePath}/capability/{call|publish}/{name}, dispatcher-code → HTTP-status mapping, 1 MiB body cap, optional verifyRequest hook. Re-exported from lib/runtime/index.{js,d.ts}.

- Browser SDK (web/client.js, web/index.d.ts) now multi-transport: connect() / RosClient accept `string | { http, ws }` and pick the transport from the URL scheme. http:// derives a sibling ws:// URL and opens it lazily on first subscribe(). New _HttpLink uses fetch() and surfaces structured errors (network_error, invalid_response, http_<status>).

- Tests: test/test-web-http.js (+423, 23 cases covering wire format, SDK, and defensive paths). test-web.js → test-web-ws.js.

- CI: suppress two Node-internal LSan reports (ContextifyContext, ContextifyScript) triggered once we load web/client.js as ESM and call fetch() — singletons retained for process lifetime.

- Drop unused WebSocketConnection export from transports/ws.js.

Fix: #1510

Author: minggangw

lib/runtime/index.d.ts

@@ -104,6 +104,20 @@ export class WebSocketTransport extends TransportAdapter {
   path: string;
 }
 
+export interface HttpTransportOptions {
+  port?: number;
+  host?: string;
+  basePath?: string;
+  verifyRequest?: (req: import('http').IncomingMessage) => boolean;
+}
+
+export class HttpTransport extends TransportAdapter {
+  constructor(options?: HttpTransportOptions);
+  port: number;
+  host: string;
+  basePath: string;
+}
+
 export interface CreateRuntimeOptions {
   node: Node;
   transport?: TransportAdapter;

lib/runtime/index.js

@@ -13,6 +13,7 @@ const { Dispatcher } = require('./dispatcher.js');
 const { Connection } = require('./connection.js');
 const { TransportAdapter } = require('./transport_adapter.js');
 const { WebSocketTransport } = require('./transports/ws.js');
+const { HttpTransport } = require('./transports/http.js');
 
 /**
  * The Web Runtime composes a capability registry, a dispatcher, and one or
@@ -134,4 +135,5 @@ module.exports = {
   Connection,
   TransportAdapter,
   WebSocketTransport,
+  HttpTransport,
 };