Make MCP server browser-portable with a Web-standard handler

Replace the Hono-only Node handler with a Fetch-API handler that runs on
Node, Bun, Deno, Cloudflare Workers, and in-page Web Workers. Restructure
@eclipse-glsp/server-mcp into a browser/common/node split mirroring
@eclipse-glsp/server.

- New browser entry point with a Web Worker integration helper.
- VS Code web-extension bundle no longer transitively pulls Node-only deps.
- Mutating tools report dispatched-command counts for cross-call
  undo / redo.
- Port-agnostic Host-header validation — matches the SDK's older
  Express middleware that the Fetch transport regressed.
- Workflow example ships an end-to-end browser demo of the portable
  handler.
- Non-loopback auth and shared session state remain adopter responsibility.
- ARCHITECTURE.md refreshed for the portable handler and for the IDE
  integrations that now register the GLSP MCP server with the host IDE.

Part of eclipse-glsp/glsp#1546

Author: martin-fleck-at

.gitignore

@@ -19,6 +19,9 @@ wf-glsp-server-node.js
 wf-glsp-server-node.js.map
 wf-glsp-server-webworker.js
 wf-glsp-server-webworker.js.map
+examples/workflow-server-bundled-web/mcp-service-worker.js
+examples/workflow-server-bundled-web/index.bundle.js
+examples/workflow-server-bundled-web/index.bundle.js.map
 
 .claude/settings.local.json
 CLAUDE.local.md

examples/workflow-server-bundled-web/README.md

@@ -14,6 +14,32 @@ See [our project website](https://www.eclipse.org/glsp/documentation/#workflowov
 
 <https://user-images.githubusercontent.com/588090/154459938-849ca684-11b3-472c-8a59-98ea6cb0b4c1.mp4>
 
+## MCP demo page
+
+`index.html` is a self-contained dev demo for the `@eclipse-glsp/server-mcp` portable Fetch
+handler. The page acts as a minimal GLSP JSON-RPC client opening a workflow session in the
+in-page Web Worker, and as an MCP client whose `fetch('/mcp', ...)` calls are intercepted by
+`mcp-service-worker.js` (shipped by `@eclipse-glsp/server-mcp/static/`, emitted next to the
+Worker bundle at build time) and proxied via `MessageChannel` to the same Worker. The Worker
+hosts `BrowserMcpServerModule`, and the launcher's `handleRequest(req)` services the proxied
+request — the same path adopters use when wiring the handler into their own Service Worker or
+edge runtime.
+
+Build (worker bundle), then serve over HTTP (Service Workers don't load from `file://`):
+
+```bash
+yarn workspace @eclipse-glsp-examples/workflow-server build
+yarn workspace @eclipse-glsp-examples/workflow-server-bundled-web start
+```
+
+Open `http://localhost:8000/` in Chromium. The page auto-renders the loaded workflow. Step
+through the buttons to exercise MCP tools against the live session; **Create task** /
+**Move last task** / **Delete last task** mutate the diagram via MCP, which auto-re-renders.
+
+The on-page SVG is a minimal schematic renderer — it is **not** the GLSP client and does not
+exercise Sprotty. Its only purpose is to make the MCP handlers' output visible so the demo can
+be eyeballed end-to-end.
+
 ## More information
 
 For more information, please visit the [Eclipse GLSP Umbrella repository](https://github.com/eclipse-glsp/glsp) and the [Eclipse GLSP Website](https://www.eclipse.org/glsp/).