Add NexusAI: universal MCP service (TTS/STT/image/video/music/web-search)

Monorepo-lite with shared @nexusai/core and @nexusai/mcp-server (stdio).
Provider-agnostic tools with explicit provider selection; NordRouter adapter
(media generate/poll/download, estimate, upload, models) and search via
perplexity/sonar. Local STT via faster-whisper uv sidecar. SQLite journal of
every generation for usage stats and future admin. 10 MCP tools.

NexusAI/package.json

@@ -0,0 +1,18 @@
+{
+  "name": "nexusai",
+  "version": "0.1.0",
+  "private": true,
+  "description": "Universal MCP service for agents: TTS, STT, image/video/music generation and web search",
+  "workspaces": [
+    "packages/core",
+    "packages/mcp-server"
+  ],
+  "scripts": {
+    "build": "npm run build --workspace @nexusai/core && npm run build --workspace @nexusai/mcp-server",
+    "build:core": "npm run build --workspace @nexusai/core",
+    "build:mcp": "npm run build --workspace @nexusai/mcp-server",
+    "start": "node packages/mcp-server/dist/index.js",
+    "dev": "npm run build && node packages/mcp-server/dist/index.js"
+  },
+  "license": "MIT"
+}