feat: initial CodeBoard monorepo scaffold

Turborepo monorepo with npm workspaces:
- apps/web: Next.js 14 frontend with Tailwind v4, SSE progress, doc viewer
- apps/worker: BullMQ job processor (clone → parse → LLM generate)
- packages/shared: TypeScript types
- packages/parser: Babel-based AST parser (JS/TS) + regex (Python)
- packages/llm: OpenAI/Anthropic provider abstraction + prompt pipeline
- packages/diagrams: Mermaid architecture & dependency graph generators
- packages/database: Prisma schema (PostgreSQL)
- Docker multi-stage build (web + worker targets)

All packages compile successfully with tsc and next build.

apps/web/package.json

@@ -0,0 +1,33 @@
+{
+  "name": "@codeboard/web",
+  "version": "0.0.1",
+  "private": true,
+  "scripts": {
+    "dev": "next dev",
+    "build": "next build",
+    "start": "next start",
+    "lint": "next lint",
+    "db:generate": "prisma generate --schema=../../packages/database/prisma/schema.prisma",
+    "db:push": "prisma db push --schema=../../packages/database/prisma/schema.prisma"
+  },
+  "dependencies": {
+    "@codeboard/shared": "*",
+    "bullmq": "^5.34.0",
+    "ioredis": "^5.4.0",
+    "lucide-react": "^0.563.0",
+    "mermaid": "^11.4.0",
+    "next": "^14.2.0",
+    "react": "^18.3.0",
+    "react-dom": "^18.3.0",
+    "react-markdown": "^9.0.0"
+  },
+  "devDependencies": {
+    "@tailwindcss/postcss": "^4.0.0",
+    "@types/node": "^20.0.0",
+    "@types/react": "^18.3.0",
+    "@types/react-dom": "^18.3.0",
+    "postcss": "^8.5.0",
+    "tailwindcss": "^4.0.0",
+    "typescript": "^5.7"
+  }
+}