refactor: move pushover into sub package, pull config into config package

Signed-off-by: Alix von Schirp <github@avonschirp.bootmedia.de>

config/eslint.config.mjs

@@ -0,0 +1,18 @@
+import globals from "globals";
+import pluginJs from "@eslint/js";
+import tseslint from "typescript-eslint";
+import eslintConfigPrettier from "eslint-config-prettier";
+import onlyWarn from "eslint-plugin-only-warn";
+
+/** @type {import('eslint').Linter.Config[]} */
+export default [
+  { languageOptions: { globals: globals.node } },
+  pluginJs.configs.recommended,
+  ...tseslint.configs.recommended,
+  eslintConfigPrettier,
+  {
+    plugins: {
+      onlyWarn,
+    },
+  },
+];