Add resilient setup script with pnpm auto-install

- scripts/setup.sh: Checks for pnpm, installs via corepack/npm if missing
- package.json: Updated to call bash script instead of node directly
- README.md: Updated with better quick start and troubleshooting

package.json

@@ -4,11 +4,8 @@
   "description": "Standard issue-based workflow template for teams",
   "private": true,
   "scripts": {
-    "setup": "node .hooks/issue-linter.js --setup",
+    "setup": "bash scripts/setup.sh",
     "validate:issues": "node .hooks/issue-linter.js",
     "test": "echo \"Add your test commands here\""
-  },
-  "devDependencies": {
-    "pre-commit-hook": "^3.0.0"
   }
 }