Add Makefile with check, lint, test, fmt targets

- check: default target, runs fmt-check, lint, and test
- fmt-check: verifies code is properly formatted
- fmt: formats code with gofmt
- lint: runs golangci-lint
- test: runs go test
- build: builds pixad binary with version info
- clean: removes build artifacts

Makefile

@@ -0,0 +1,38 @@
+.PHONY: check lint test fmt build clean
+
+VERSION := $(shell git describe --tags --always --dirty 2>/dev/null || echo "dev")
+BUILDARCH := $(shell go env GOARCH)
+LDFLAGS := -X main.Version=$(VERSION) -X main.Buildarch=$(BUILDARCH)
+
+# Default target: run all checks
+check: fmt-check lint test
+
+# Check formatting without modifying files
+fmt-check:
+	@echo "Checking formatting..."
+	@test -z "$$(gofmt -l .)" || (echo "Files need formatting:"; gofmt -l .; exit 1)
+
+# Format code
+fmt:
+	@echo "Formatting code..."
+	gofmt -w .
+
+# Run linter
+lint:
+	@echo "Running linter..."
+	golangci-lint run
+
+# Run tests
+test:
+	@echo "Running tests..."
+	go test -v ./...
+
+# Build the binary
+build:
+	@echo "Building pixad..."
+	go build -ldflags "$(LDFLAGS)" -o bin/pixad ./cmd/pixad
+
+# Clean build artifacts
+clean:
+	rm -rf bin/
+	rm -f data.db

TODO.md

@@ -3,7 +3,7 @@
 A single linear checklist of tasks to implement the complete pixa caching image reverse proxy server.
 
 ## Project Setup
-- [ ] Create Makefile with check, lint, test, fmt targets
+- [x] Create Makefile with check, lint, test, fmt targets
 - [ ] Create project structure (cmd/pixad, internal/*)
 - [ ] Implement globals package
 - [ ] Implement logger package