chore: fix .gitignore and stop tracking build artifacts

The .gitignore previously contained the literal echo command instead of its
output, so appro-admin.zip slipped past it. Rewrite it properly and untrack
the build zip and tsconfig.tsbuildinfo (kept on disk, ignored going forward).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

.gitignore

@@ -1,10 +1,12 @@
-# Create or edit .gitignore
+# Next.js build output
-echo "# Next.js build output
 .next/
 .next/**
 .next/dev/lock
 out
 appro-admin
+appro-admin.zip
+*.zip
+
 # Dependencies
 node_modules/
 
@@ -27,4 +29,7 @@ yarn-error.log*
 *.ntvs*
 *.njsproj
 *.sln
-*.sw?" >> .gitignore
+*.sw?
+
+# TypeScript
+tsconfig.tsbuildinfo