cleanup: Remove unused files and fix ETHOS violations

Remove unused generation scripts (not referenced):
- scripts/generate-keypair.go (unused manual utility)
- cmd/tools/keygen/ (unused utility, clutters cmd structure)

Remove root-level dev files (clutter):
- restart_and_fix.sh (dangerous: wipes database)
- test_install_commands.sh (development only)
- test-binary (compiled artifact)
- sudo (third-party tool)
- scanning_ux_summary.txt (dev notes)

Fix ETHOS violations in build-secure-agent.sh:
- Remove emojis (🔨, ✅, ℹ️)
- Replace with proper format: [INFO] [build] ...

Cleanup based on definitive code forensics.

Impact: Cleaner repository, ETHOS-compliant, no functional loss.

scripts/build-secure-agent.sh

@@ -4,11 +4,11 @@
 
 set -e
 
-echo "🔨 RedFlag Agent Build"
-echo "====================="
+echo "[INFO] [build] RedFlag Agent Build"
+echo "================================="
 
 # Build agent
-echo "Building agent..."
+echo "[INFO] [build] Building agent..."
 cd aggregator-agent
 
 go build \
@@ -17,7 +17,7 @@ go build \
 
 cd ..
 
-echo "✅ Agent build complete!"
+echo "[INFO] [build] Agent build complete!"
 echo "   Binary: aggregator-agent/redflag-agent"
 echo ""
-echo "ℹ️  Note: Agent will fetch the server's public key automatically at startup"
+echo "[INFO] [build] Note: Agent will fetch the server's public key automatically at startup"