Add Dev Container configuration

.devcontainer/Dockerfile

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+FROM mcr.microsoft.com/devcontainers/java:1-17-bullseye
+
+RUN mkdir /home/vscode/.m2 && \
+    chown -R vscode:vscode /home/vscode/.m2

.devcontainer/devcontainer.json

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+{
+	"name": "doma-spring-boot",
+	"build": {
+		"dockerfile": "Dockerfile"
+	},
+	"features": {
+		// Since the base image is Java 17, set the version to "none" so Java is not installed here.  
+		// However, using SDKMAN! is convenient, so we still use ghcr.io/devcontainers/features/java.
+		"ghcr.io/devcontainers/features/java:1": {
+			"version": "none"
+		},
+		// For using Testcontainers.
+		"ghcr.io/devcontainers/features/docker-in-docker:2": {},
+		// For using pre-commit.
+		"ghcr.io/devcontainers/features/python:1": {
+			"version": "3.12",
+			"toolsToInstall": "pre-commit"
+		}
+	},
+	"mounts": [
+		{
+			"source": "doma-spring-boot-maven",
+			"target": "/home/vscode/.m2",
+			"type": "volume"
+		},
+		{
+			"source": "doma-spring-boot-dind",
+			"target": "/var/lib/docker",
+			"type": "volume"
+		}
+	],
+	"postCreateCommand": ".devcontainer/setup.sh",
+	"customizations": {
+		"vscode": {
+			"extensions": [
+				"vmware.vscode-boot-dev-pack",
+				"redhat.vscode-xml",
+				"redhat.vscode-yaml"
+			]
+		}
+	}
+}

.devcontainer/setup.sh

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+#!/bin/bash
+pre-commit install -t pre-commit -t pre-push

.pre-commit-config.yaml

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+repos:
+
+  - repo: local
+    hooks:
+      - id: format
+        name: Format Java source code
+        entry: ./mvnw formatter:format -q
+        types:
+          - java
+        language: system
+        pass_filenames: false
+        stages:
+          - pre-commit
+
+  - repo: local
+    hooks:
+      - id: verify
+        name: Verify
+        entry: ./mvnw verify
+        language: system
+        pass_filenames: false
+        stages:
+          - pre-push