feat(storage): remove upload-size cap, add MB/GB unit toggle

Storage panel's max-upload-size input now accepts any positive integer
(bounded only by JS safe-integer ceiling) and offers an MB/GB unit
toggle. Multipart limit relaxed to MAX_SAFE_INTEGER — actual cap is
enforced per-request from the DB setting, not at the framework layer.

packages/server/src/index.ts

@@ -65,7 +65,7 @@ async function main(): Promise<void> {
 
   await app.register(multipart, {
     limits: {
-      fileSize: 5 * 1024 * 1024 * 1024,  // 5GB hard ceiling — actual limit enforced per-request from DB
+      fileSize: Number.MAX_SAFE_INTEGER, // No global cap — actual limit enforced per-request from DB
     },
   });