feat: add @claudemesh/sdk package for non-Claude-Code clients

Standalone TypeScript SDK that any process can use to join a mesh and
send/receive messages. Implements the same WS protocol and libsodium
crypto_box encryption as the CLI, with an EventEmitter-based API.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/connector-slack/package.json

@@ -0,0 +1,26 @@
+{
+  "name": "@claudemesh/connector-slack",
+  "version": "0.1.0",
+  "description": "Slack connector for claudemesh — relay messages between Slack channels and mesh peers",
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "scripts": {
+    "build": "tsc",
+    "start": "node dist/index.js"
+  },
+  "dependencies": {
+    "@slack/web-api": "^7.0.0",
+    "@slack/socket-mode": "^2.0.0",
+    "ws": "^8.0.0",
+    "tweetnacl": "^1.0.3",
+    "tweetnacl-util": "^0.15.1"
+  },
+  "devDependencies": {
+    "@types/ws": "^8.0.0",
+    "typescript": "^5.0.0"
+  },
+  "engines": {
+    "node": ">=18"
+  },
+  "license": "MIT"
+}