feat: implement playground app with AI SDK v6 tool execution

- Create new Next.js app at apps/playground for testing TPMJS tools
- Implement AI SDK v6 patterns with DefaultChatTransport and UIMessage format
- Create template tool package at packages/tools/hello with hello-world and hello-name tools
- Use tool() and jsonSchema() helpers to avoid Zod 4 conversion issues with OpenAI
- Add static tool loading system with switch statement (Next.js/webpack compatible)
- Implement chat interface with tool call visualization showing inputs/outputs
- Support multi-step tool execution with stepCountIs(5)
- Stream responses with toUIMessageStreamResponse() for full tool support
- Add sidebar showing available tools (static list)
- Use parts-based message rendering for text and tool calls
- Integrate firecrawl-aisdk tools (scrape, crawl, search)
- Add theme toggle in header (defaults to light mode)
- Fix responsive layout with max-width for message bubbles
- Use biome-ignore comments for legitimate any types in tool loading

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

packages/tools/hello/package.json

@@ -0,0 +1,27 @@
+{
+  "name": "@tpmjs/hello",
+  "version": "0.0.1",
+  "private": true,
+  "description": "Example TPMJS tools - Hello World and Hello Name",
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "scripts": {
+    "build": "tsc",
+    "dev": "tsc --watch",
+    "clean": "rm -rf dist",
+    "type-check": "tsc --noEmit"
+  },
+  "keywords": ["tpmjs-tool", "ai-sdk", "hello", "example"],
+  "tpmjs": {
+    "category": "text-analysis",
+    "description": "Simple greeting tools - Hello World and personalized Hello Name greetings"
+  },
+  "dependencies": {
+    "ai": "6.0.0-beta.124"
+  },
+  "devDependencies": {
+    "@tpmjs/tsconfig": "workspace:*",
+    "typescript": "^5.9.3"
+  },
+  "files": ["dist", "README.md"]
+}