WIP: Migrate servers to McpServer with registerTool/registerResource/registerPrompt APIs

Progress so far:
- Sequential thinking: Converted to McpServer with Zod schemas (complete)
- Memory: Converted to use registerTool API (needs Zod conversion)
- Filesystem: Converted to use registerTool API (needs Zod conversion)
- Everything: Converted to use register* APIs (needs Zod conversion)

Key learnings:
- registerTool/registerResource/registerPrompt only exist on McpServer class
- McpServer expects Zod schemas, not JSON schemas
- Updated SDK versions to ^1.20.1 for all servers

Status: Work in progress - code does not compile yet
Next steps: Convert remaining servers' JSON schemas to Zod schemas

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

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

src/sequentialthinking/package.json

@@ -21,7 +21,8 @@
   "dependencies": {
     "@modelcontextprotocol/sdk": "^1.20.1",
     "chalk": "^5.3.0",
-    "yargs": "^17.7.2"
+    "yargs": "^17.7.2",
+    "zod": "^3.23.8"
   },
   "devDependencies": {
     "@types/node": "^22",