feat(wiki): enable image uploads via server actions

Raise the serverActions request body limit to 10mb so wiki image uploads
(capped at 8mb in uploadWikiImage) pass through with room for multipart
overhead.

next.config.mjs

@@ -3,13 +3,18 @@ import path from "node:path";
 import { fileURLToPath } from "node:url";
 import packageJson from "./package.json" with { type: "json" };
 
-
 /** @type {import('next').NextConfig} */
 const nextConfig = {
   // Your Next.js config here
   env: {
     version: packageJson.version,
   },
+  // Server Actions default to a 1 MB request body limit, which would reject
+  // most image uploads. Bump it so wiki image uploads (capped at 8 MB in the
+  // uploadWikiImage action) pass through with room for multipart overhead.
+  serverActions: {
+    bodySizeLimit: "10mb",
+  },
   // Pin the workspace root to this repo dir so the standalone build emits a
   // flat .next/standalone/server.js (Next otherwise walks up looking for
   // lockfiles and can pick a parent directory — here a stray