Add .devcontainer/ (#2)

.devcontainer/Dockerfile

@@ -0,0 +1,7 @@
+FROM tinygo/tinygo-dev
+
+RUN go install golang.org/x/tools/gopls@latest && \
+    go install golang.org/x/tools/cmd/goimports@latest && \
+    go install github.com/sago35/tinygo-autocmpl@latest
+
+RUN echo 'eval "$(tinygo-autocmpl --completion-script-bash)"' >> ~/.bashrc

.devcontainer/devcontainer.json

@@ -0,0 +1,36 @@
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the README at:
+// https://github.com/microsoft/vscode-dev-containers/tree/v0.234.0/containers/docker-existing-dockerfile
+{
+	"name": "Existing Dockerfile",
+
+	// Sets the run context to one level up instead of the .devcontainer folder.
+	"context": "..",
+
+	// Update the 'dockerFile' property if you aren't using the standard 'Dockerfile' filename.
+	"dockerFile": "./Dockerfile",
+
+	// Set *default* container specific settings.json values on container create.
+	"settings": {},
+
+	// Add the IDs of extensions you want installed when the container is created.
+	"extensions": [
+		"golang.go",
+		"tinygo.vscode-tinygo"
+	],
+
+	// Use 'forwardPorts' to make a list of ports inside the container available locally.
+	// "forwardPorts": [],
+
+	// Uncomment the next line to run commands after the container is created - for example installing curl.
+	// "postCreateCommand": "apt-get update && apt-get install -y curl",
+	"postCreateCommand": "rm -f ./.vscode/settings.json"
+
+	// Uncomment when using a ptrace-based debugger like C++, Go, and Rust
+	// "runArgs": [ "--cap-add=SYS_PTRACE", "--security-opt", "seccomp=unconfined" ],
+
+	// Uncomment to use the Docker CLI from inside the container. See https://aka.ms/vscode-remote/samples/docker-from-docker.
+	// "mounts": [ "source=/var/run/docker.sock,target=/var/run/docker.sock,type=bind" ],
+
+	// Uncomment to connect as a non-root user if you've added one. See https://aka.ms/vscode-remote/containers/non-root.
+	// "remoteUser": "vscode"
+}