Update to use ESLint 9 and Prettier 3 (#504)

teammapper-backend/eslint.config.cjs

@@ -0,0 +1,78 @@
+const { fixupConfigRules, fixupPluginRules } = require("@eslint/compat");
+const tseslint = require("typescript-eslint");
+const jest = require("eslint-plugin-jest");
+const importPlugin = require("eslint-plugin-import");
+const globals = require("globals");
+const tsParser = require("@typescript-eslint/parser");
+const js = require("@eslint/js");
+const prettier = require("eslint-plugin-prettier");
+const stylisticTs = require("@stylistic/eslint-plugin-ts");
+
+const { FlatCompat } = require("@eslint/eslintrc");
+
+const compat = new FlatCompat({
+    baseDirectory: __dirname,
+    recommendedConfig: js.configs.recommended,
+    allConfig: js.configs.all
+});
+
+module.exports = [
+    {
+        ignores: ["src/migrations/**/*", "dist/**/*", "src/jobs/**/*"],
+    },
+    js.configs.recommended,
+    importPlugin.flatConfigs.recommended,
+    ...tseslint.configs.recommended,
+    {
+        files: ["**/*.ts"],
+        plugins: {
+            jest: jest,
+            prettier: prettier,
+            "@stylistic/ts": stylisticTs
+        },
+        languageOptions: {
+            globals: {
+                ...jest.environments.globals.globals,
+                ...globals.node,
+            },
+            parser: tsParser,
+            parserOptions: {
+                project: ["tsconfig.json"],
+                ecmaVersion: 12,
+                sourceType: "module",
+            },
+        },
+        settings: {
+            "import/resolver": {
+                typescript: {},
+                node: {
+                    extensions: [".js", ".ts"],
+                    moduleDirectory: ["node_modules", "src/"],
+                },
+            },
+        },
+        rules: {
+            "@typescript-eslint/no-explicit-any": "warn",
+            "prettier/prettier": "error",
+            "no-unused-vars": "off",
+            "@stylistic/ts/member-delimiter-style": ["error", {
+                "multiline": {
+                    "delimiter": "none",
+                    "requireLast": true
+                },
+                "singleline": {
+                    "delimiter": "semi",
+                    "requireLast": false
+                },
+                "multilineDetection": "brackets"
+            }],
+            "@typescript-eslint/no-unused-vars": ["error", {
+                argsIgnorePattern: "^_",
+            }],
+            "import/extensions": ["error", "ignorePackages", {
+                js: "never",
+                ts: "never",
+            }],
+        },
+    },
+];