build: migrate eslint to v9

eslint.config.mjs

@@ -0,0 +1,74 @@
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+import js from "@eslint/js";
+import { FlatCompat } from "@eslint/eslintrc";
+
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const compat = new FlatCompat({
+    baseDirectory: __dirname,
+    recommendedConfig: js.configs.recommended,
+    allConfig: js.configs.all
+});
+
+export default [{
+    ignores: [
+        "**/node_modules",
+        "**/package-lock.json",
+        "**/documentation",
+        "**/e2e",
+        "src/setupJest.ts",
+        "src/jestGlobalMocks.ts",
+        "src/environments",
+    ],
+}, {
+    files: ["**/*.js"],
+
+    languageOptions: {
+        ecmaVersion: 2018,
+        sourceType: "script",
+    },
+}, ...compat.extends(
+    "plugin:@angular-eslint/recommended",
+    "plugin:@typescript-eslint/recommended",
+    "prettier",
+).map(config => ({
+    ...config,
+    files: ["**/*.ts"],
+})), {
+    files: ["**/*.ts"],
+
+    languageOptions: {
+        ecmaVersion: 5,
+        sourceType: "script",
+
+        parserOptions: {
+            project: ["tsconfig.*?.json"],
+            createDefaultProgram: true,
+        },
+    },
+
+    rules: {
+        "@angular-eslint/component-class-suffix": ["error", {
+            suffixes: ["Component", "Page"],
+        }],
+
+        "@angular-eslint/directive-selector": ["error", {
+            type: "attribute",
+            prefix: "app",
+            style: "camelCase",
+        }],
+
+        "@angular-eslint/component-selector": ["error", {
+            type: "element",
+            prefix: "app",
+            style: "kebab-case",
+        }],
+    },
+}, ...compat.extends("plugin:@angular-eslint/template/recommended").map(config => ({
+    ...config,
+    files: ["**/*.html"],
+})), ...compat.extends("plugin:@angular-eslint/template/process-inline-templates").map(config => ({
+    ...config,
+    files: ["**/*.component.ts"],
+}))];