feat(categories): kategori ağacı, varsayılan Türkçe set ve yönetim ekranı

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/shared/schemas/category.ts

@@ -0,0 +1,20 @@
+import { z } from "zod";
+import { tr } from "../../i18n/tr";
+import { ICON_KEYS, SWATCHES } from "../appearance";
+
+export const CATEGORY_KINDS = ["expense", "income"] as const;
+export type CategoryKind = (typeof CATEGORY_KINDS)[number];
+
+export const categoryFormSchema = z.object({
+  kind: z.enum(CATEGORY_KINDS),
+  name: z.string().trim().min(1, tr.common.required).max(80, tr.validation.nameMax),
+  parentId: z
+    .string()
+    .regex(/^([a-f0-9]{24})?$/i)
+    .transform((s) => (s === "" ? null : s)),
+  icon: z.enum(ICON_KEYS),
+  color: z.enum(SWATCHES),
+});
+
+export type CategoryFormInput = z.input<typeof categoryFormSchema>;
+export type CategoryForm = z.output<typeof categoryFormSchema>;