Initial commit: Nerd Monitor - Cross-platform system monitoring application

Features:
- Multi-platform agents (Linux, macOS, Windows - AMD64 & ARM64)
- Real-time CPU, RAM, and disk usage monitoring
- Responsive web dashboard with live status indicators
- Session-based authentication with secure credentials
- Stale agent detection and removal (6+ months inactive)
- Auto-refresh dashboard (5 second intervals)
- 15-second agent reporting intervals
- Auto-generated agent IDs from hostnames
- In-memory storage (zero database setup)
- Minimal dependencies (Chi router + Templ templating)

Project Structure:
- cmd/: Agent and Server executables
- internal/: API, Auth, Stats, Storage, and UI packages
- views/: Templ templates for dashboard UI
- Makefile: Build automation for all platforms

Ready for deployment with comprehensive documentation:
- README.md: Full project documentation
- QUICKSTART.md: Getting started guide
- AGENTS.md: Development guidelines

Makefile

@@ -0,0 +1,55 @@
+.PHONY: build build-server build-agent build-all clean templ help
+
+# Default target
+help:
+	@echo "Nerd Monitor - Build Commands"
+	@echo ""
+	@echo "  make build          - Build server and agent for current OS"
+	@echo "  make build-server   - Build server executable"
+	@echo "  make build-agent    - Build agent executable"
+	@echo "  make build-all      - Build for all platforms (Linux, macOS, Windows)"
+	@echo "  make templ          - Generate code from Templ templates"
+	@echo "  make clean          - Remove build artifacts"
+	@echo ""
+
+build: templ build-server build-agent
+
+templ:
+	@echo "Generating Templ templates..."
+	@go run github.com/a-h/templ/cmd/templ@latest generate
+
+build-server: templ
+	@echo "Building server for $(GOOS)/$(GOARCH)..."
+	@mkdir -p bin
+	go build -o bin/nerd-monitor-server ./cmd/server
+
+build-agent:
+	@echo "Building agent for $(GOOS)/$(GOARCH)..."
+	@mkdir -p bin
+	go build -o bin/nerd-monitor-agent ./cmd/agent
+
+build-all: templ
+	@echo "Building for all platforms..."
+	@mkdir -p bin
+	@echo "  Linux AMD64..."
+	@GOOS=linux GOARCH=amd64 go build -o bin/nerd-monitor-server-linux-amd64 ./cmd/server
+	@GOOS=linux GOARCH=amd64 go build -o bin/nerd-monitor-agent-linux-amd64 ./cmd/agent
+	@echo "  Linux ARM64..."
+	@GOOS=linux GOARCH=arm64 go build -o bin/nerd-monitor-server-linux-arm64 ./cmd/server
+	@GOOS=linux GOARCH=arm64 go build -o bin/nerd-monitor-agent-linux-arm64 ./cmd/agent
+	@echo "  macOS AMD64..."
+	@GOOS=darwin GOARCH=amd64 go build -o bin/nerd-monitor-server-darwin-amd64 ./cmd/server
+	@GOOS=darwin GOARCH=amd64 go build -o bin/nerd-monitor-agent-darwin-amd64 ./cmd/agent
+	@echo "  macOS ARM64..."
+	@GOOS=darwin GOARCH=arm64 go build -o bin/nerd-monitor-server-darwin-arm64 ./cmd/server
+	@GOOS=darwin GOARCH=arm64 go build -o bin/nerd-monitor-agent-darwin-arm64 ./cmd/agent
+	@echo "  Windows AMD64..."
+	@GOOS=windows GOARCH=amd64 go build -o bin/nerd-monitor-server-windows-amd64.exe ./cmd/server
+	@GOOS=windows GOARCH=amd64 go build -o bin/nerd-monitor-agent-windows-amd64.exe ./cmd/agent
+	@echo "Build complete!"
+	@ls -lh bin/
+
+clean:
+	@echo "Cleaning build artifacts..."
+	@rm -rf bin/
+	@echo "Clean complete!"