build(deps): update Next.js to v15 and ESLint to v9

packages/blog/eslint.config.js

@@ -0,0 +1,13 @@
+import typescriptESLint from "typescript-eslint"
+import configNextjs from "@repo/eslint-config/nextjs"
+
+export default typescriptESLint.config(...configNextjs, {
+  files: ["**/*.ts", "**/*.tsx"],
+  languageOptions: {
+    parser: typescriptESLint.parser,
+    parserOptions: {
+      projectService: true,
+      tsconfigRootDir: import.meta.dirname,
+    },
+  },
+})