Add commit hash to footer for deployment verification

- Display git commit hash in footer to track deployed version
- Create cross-platform build script to inject commit hash
- Update build process to include version information

🤖 Generated with [Claude Code](https://claude.ai/code)

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

package.json

@@ -6,12 +6,12 @@
     "dev": "next dev --turbopack -p 9002",
     "genkit:dev": "genkit start -- tsx src/ai/dev.ts",
     "genkit:watch": "genkit start -- tsx --watch src/ai/dev.ts",
-    "build": "next build",
+    "build": "node scripts/set-git-commit.js && next build",
     "build:static": "next build",
     "start": "next start",
     "lint": "next lint",
     "typecheck": "tsc --noEmit",
-    "deploy:s3": "npm run build:static && aws s3 sync out/ s3://$S3_BUCKET_NAME --delete",
+    "deploy:s3": "npm run build && aws s3 sync out/ s3://$S3_BUCKET_NAME --delete",
     "create-s3-bucket": "node scripts/create-s3-bucket.js",
     "prepare": "husky install"
   },
@@ -66,6 +66,7 @@
     "@types/react-dom": "^18",
     "aws-cdk-lib": "^2.189.1",
     "constructs": "^10.4.2",
+    "cross-env": "^7.0.3",
     "esbuild": "^0.25.5",
     "eslint": "^9.30.0",
     "eslint-config-next": "15.3.4",