[release] Drop CLI postinstall echo + remove misleading packageManager field

The CLI's postinstall was a harmless echo that pnpm 10+ flagged in the
approve-builds prompt for every consumer install. Drop it. Root
package.json declared pnpm as the package manager, but the repo actually
uses Bun (bun.lock, CI uses `bun install`) — the field was misleading
Corepack and downstream tooling. Remove it.

Author: ZachHandley

package.json

@@ -17,7 +17,6 @@
     "build": "cd packages/appwrite-utils && bun run build && cd ../appwrite-utils-helpers && bun run build && cd ../appwrite-utils-cli && bun run build && cd ../appwrite-utils-mcp && bun run build",
     "deploy": "cd packages/appwrite-utils && bun run deploy && cd ../appwrite-utils-cli && bun run deploy"
   },
-  "packageManager": "pnpm@10.11.1+sha512.e519b9f7639869dc8d5c3c5dfef73b3f091094b0a006d7317353c72b124e80e1afd429732e28705ad6bfa1ee879c1fce46c128ccebd3192101f43dd67c667912",
   "overrides": {
     "zod": "4.4.3"
   }

packages/appwrite-utils-cli/package.json

@@ -33,8 +33,7 @@
     "test": "jest",
     "test:watch": "jest --watch",
     "test:coverage": "jest --coverage",
-    "test:ci": "jest --ci --coverage --watchAll=false",
-    "postinstall": "echo 'This package is intended for CLI use only and should not be added as a dependency in other projects.'"
+    "test:ci": "jest --ci --coverage --watchAll=false"
   },
   "dependencies": {
     "@types/inquirer": "^9.0.8",