refactor: reinforce harness to prevent contract violations

- verify.sh: validate prohibited dirs, gate nomenclature, feature schema, runtime consistency
- orquestra-status: block direct writes to backlog/features.json
- install.sh: add build artifacts to .gitignore template
- AGENTS.md: document prohibited dirs, gate nomenclature, feature schema
- Reset runtime-status to idle state

scripts/install.sh

@@ -79,16 +79,39 @@ append_gitignore_block() {
   local gitignore=$1
   touch "$gitignore"
   if ! grep -q '^# BEGIN ORQUESTRA$' "$gitignore"; then
-    cat >>"$gitignore" <<'EOF'
-
+    cat >>"$gitignore" <<'INNEREOF'
 # BEGIN ORQUESTRA
 __pycache__/
 *.pyc
 .pytest_cache/
 .codegraph/
 .atl/
+
+# Build artifacts
+.next/
+dist/
+build/
+*.log
+
+# Dependencies
+node_modules/
+
+# Environment
+.env
+.env.local
+.env.*.local
+
+# IDE
+.vscode/
+.idea/
+*.swp
+*.swo
+
+# OS
+.DS_Store
+Thumbs.db
 # END ORQUESTRA
-EOF
+INNEREOF
   fi
 }