chore(cli): bundle for node, prep for npm publish

Makes @claudemesh/cli installable globally via npm without requiring
bun on user machines. (Bun stays the dev runtime; bundled output is
node-compatible.)

- bun build --target=node --outfile dist/index.js produces a 2.69MB
  standalone bundle with node-shebang banner
- package.json: add description/keywords/author/license/homepage/
  repository, set bin to ./dist/index.js, files=[dist, README, LICENSE],
  publishConfig.access=public, engines.node >=20
- prepublishOnly auto-runs the build
- pin zod from catalog: to 4.1.13 (npm rejects catalog: refs)
- swap Bun.spawnSync → node:child_process.spawnSync in install.ts
  (the only Bun-global usage in the package)
- strip shebang from src/index.ts (banner supplies it post-bundle)

install command now runs in two modes:
- BUNDLED (npm i -g): detects dist/index.js path, writes MCP entry
  with command "claudemesh" (relies on the global bin shim on PATH)
- SOURCE (bun src/index.ts, dev): preflights bun, writes MCP entry
  with command "bun <absolute-path> mcp"

verified end-to-end:
- node dist/index.js --help prints usage ✓
- node dist/index.js install writes correct ~/.claude.json ✓
- node dist/index.js mcp | tools/list returns all 5 tools ✓
- bun src/index.ts install (dev mode) still works ✓

NOT PUBLISHED YET — @claudemesh/cli is owned by an unrelated project
on npm. Awaiting user decision on alternative name (claudemesh-cli,
@alezmad/claudemesh-cli, or new org scope). Bundle is name-agnostic
and will reuse regardless.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

apps/cli/package.json

@@ -1,26 +1,55 @@
 {
   "name": "@claudemesh/cli",
   "version": "0.1.0",
-  "private": true,
+  "description": "Claude Code MCP client for claudemesh — peer mesh messaging between Claude sessions.",
+  "keywords": [
+    "claude-code",
+    "mcp",
+    "model-context-protocol",
+    "claudemesh",
+    "peer-messaging",
+    "multi-agent"
+  ],
+  "author": "Alejandro Gutiérrez",
+  "license": "MIT",
+  "homepage": "https://claudemesh.com",
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/alezmad/claudemesh.git",
+    "directory": "apps/cli"
+  },
   "type": "module",
   "bin": {
-    "claudemesh": "./src/index.ts"
+    "claudemesh": "./dist/index.js"
+  },
+  "files": [
+    "dist",
+    "README.md",
+    "LICENSE"
+  ],
+  "publishConfig": {
+    "access": "public"
   },
   "scripts": {
+    "build": "bun build src/index.ts --target=node --outfile dist/index.js --banner \"#!/usr/bin/env node\" && chmod +x dist/index.js",
     "clean": "git clean -xdf .cache .turbo dist node_modules",
     "dev": "bun --hot src/index.ts",
     "start": "bun src/index.ts",
     "format": "prettier --check . --ignore-path ../../.gitignore",
     "lint": "eslint",
+    "prepublishOnly": "bun run build",
     "test": "vitest run",
     "typecheck": "tsc --noEmit"
   },
   "prettier": "@turbostarter/prettier-config",
+  "engines": {
+    "node": ">=20"
+  },
   "dependencies": {
     "@modelcontextprotocol/sdk": "1.27.1",
     "libsodium-wrappers": "0.7.15",
     "ws": "8.20.0",
-    "zod": "catalog:"
+    "zod": "4.1.13"
   },
   "devDependencies": {
     "@turbostarter/eslint-config": "workspace:*",