Basic golang CI setup (#360)

* bskyweb: Makefile and dev env

This matches the setup for local dev testing in atproto and indigo
repos.

* gitignore: don't ignore self and .github/

* CI: golang build+test and lint actions

* bskyweb: better use of godotenv

A recent change from indigo.

* prettier: ignore top-level app.json

* CI: bump from golang 1.19 to 1.20

* bskyweb: update to golang 1.20

bskyweb/Makefile

@@ -0,0 +1,42 @@
+
+SHELL = /bin/bash
+.SHELLFLAGS = -o pipefail -c
+
+.PHONY: help
+help: ## Print info about all commands
+	@echo "Commands:"
+	@echo
+	@grep -E '^[a-zA-Z0-9_-]+:.*?## .*$$' $(MAKEFILE_LIST) | awk 'BEGIN {FS = ":.*?## "}; {printf "    \033[01;32m%-20s\033[0m %s\n", $$1, $$2}'
+
+.PHONY: build
+build: ## Build all executables
+	go build ./cmd/bskyweb
+
+.PHONY: test
+test: ## Run all tests
+	go test ./...
+
+.PHONY: coverage-html
+coverage-html: ## Generate test coverage report and open in browser
+	go test ./... -coverpkg=./... -coverprofile=test-coverage.out
+	go tool cover -html=test-coverage.out
+
+.PHONY: lint
+lint: ## Verify code style and run static checks
+	go vet ./...
+	test -z $(gofmt -l ./...)
+
+.PHONY: fmt
+fmt: ## Run syntax re-formatting (modify in place)
+	go fmt ./...
+
+.PHONY: check
+check: ## Compile everything, checking syntax (does not output binaries)
+	go build ./...
+
+.env:
+	if [ ! -f ".env" ]; then cp example.dev.env .env; fi
+
+.PHONY: run-dev-bskyweb
+run-dev-bskyweb: .env ## Runs 'bskyweb' for local dev
+	GOLOG_LOG_LEVEL=info go run ./cmd/bskyweb serve