fix(sea-builder): add postject as catalog devDependency

Add postject to pnpm catalog and reference it in node-sea-builder to
ensure it's available via pnpm exec on all platforms, particularly
Windows where PATH resolution can differ from Linux/macOS.

This fixes Windows SEA builds failing with:
"postject is required to inject the SEA blob into the Node.js binary"

The dependency was already in the root package.json but wasn't being
resolved properly by pnpm exec postject on Windows runners.

Changes:
- Add postject: 1.0.0-alpha.6 to pnpm-workspace.yaml catalog
- Reference postject: catalog: in node-sea-builder package.json

Author: jdalton

packages/node-sea-builder/package.json

@@ -4,6 +4,7 @@
   },
   "description": "Native Node.js SEA binary builder (fallback)",
   "devDependencies": {
+    "postject": "catalog:",
     "vitest": "3.0.0"
   },
   "license": "MIT",

pnpm-lock.yaml

@@ -7,3 +7,4 @@ catalog:
   '@socketsecurity/lib': 2.2.0
   '@socketsecurity/registry': 2.0.0
   '@socketsecurity/sdk': 3.0.7
+  postject: 1.0.0-alpha.6