feat: choose a product's category from the ones T5DE has seen

A product can be filed under another IMVU category than its parent's: any category path the hub has seen on a
revision's parent (and each step of it), within the parent's top-level category, so it stays the same kind of
product (the proxy tells clothing, furniture and rooms apart by category). It's an info field like the others:
lockable, in the history, undone by the same rules. Lists filter by the chosen path, and products show it.

Co-Authored-By: Claude Opus 5.5 <[email protected]>

apps/web/app/products/actions.ts

@@ -85,6 +85,7 @@ export async function saveProduct(_: ActionState, form: FormData): Promise<Actio
             }
           : {}),
         ...(listed === "yes" || listed === "no" ? { listed: listed === "yes" } : {}),
+        ...(has("category") ? { category: Number(field(form, "category")) || null } : {}),
         ...(field(form, "reason") ? { reason: field(form, "reason") } : {}),
       }),
     );
@@ -110,9 +111,11 @@ export async function publishProduct(_: ActionState, form: FormData): Promise<Ac
 /** Moderators lock fields: the checked ones are locked, the rest unlocked. */
 export async function saveLocks(_: ActionState, form: FormData): Promise<ActionState> {
   const id = field(form, "id");
-  const fields = form.getAll("locked").filter((v): v is "name" | "description" | "rating" | "tags" | "listed" =>
-    ["name", "description", "rating", "tags", "listed"].includes(String(v)),
-  );
+  const fields = form
+    .getAll("locked")
+    .filter((v): v is "name" | "description" | "rating" | "tags" | "listed" | "category" =>
+      ["name", "description", "rating", "tags", "listed", "category"].includes(String(v)),
+    );
   return attempt(async () => {
     unwrap(await api.products({ id }).locks.put({ fields, reason: field(form, "reason") }));
     done(id);