refactor(ts): complete legacy host removal — drop fastify/commander/zod, delete MCP SDK server, remove ManagedRuntime facades

Finishes the remaining EFFECT_NATIVE_REWRITE_PLAN stages in one verified slice:
- fastify, @fastify/websocket, commander, zod removed from all package manifests
- legacy @modelcontextprotocol/sdk stdio server deleted; effect/unstable/ai McpServer is canonical
- no ManagedRuntime or Effect.runPromise program facades remain in production source
- gateway server/rpc-contract and client rpc/socket moved onto Effect v4 native http/rpc/socket layers

Gates (force-run, no cache): check:tsgo, build, test (96 tests / 11 tasks) all green.
Native-class inventory: zero blocking production classes.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

ts/packages/workbench/package.json

@@ -10,21 +10,11 @@
     "qa:browser": "playwright test"
   },
   "dependencies": {
-    "@effect/ai-anthropic": "4.0.0-beta.78",
-    "@effect/ai-openai": "4.0.0-beta.78",
-    "@effect/ai-openrouter": "4.0.0-beta.78",
     "@effect/atom-react": "4.0.0-beta.78",
-    "@effect/openapi-generator": "4.0.0-beta.78",
-    "@effect/opentelemetry": "4.0.0-beta.78",
     "@effect/platform-browser": "4.0.0-beta.78",
-    "@effect/platform-bun": "4.0.0-beta.78",
-    "@effect/platform-node": "4.0.0-beta.78",
-    "@effect/platform-node-shared": "4.0.0-beta.78",
-    "@effect/tsgo": "0.14.0",
-    "@effect/vitest": "4.0.0-beta.78",
-    "@tanstack/react-query": "^5.75.0",
     "@trustgraph/client": "workspace:*",
     "clsx": "^2.1.0",
+    "effect": "4.0.0-beta.78",
     "lucide-react": "^0.513.0",
     "react": "^19.1.0",
     "react-dom": "^19.1.0",
@@ -32,8 +22,7 @@
     "react-force-graph-2d": "^1.29.1",
     "react-markdown": "^10.1.0",
     "react-router": "^7.6.0",
-    "tailwind-merge": "^3.3.0",
-    "zustand": "^5.0.0"
+    "tailwind-merge": "^3.3.0"
   },
   "devDependencies": {
     "@effect/vitest": "4.0.0-beta.78",