Initial scaffold for AvtoAmbor parts inventory

SvelteKit 2 + Svelte 4 + adapter-node, SQLite via better-sqlite3 (WAL,
foreign keys on). Bilingual EN/Тоҷикӣ throughout, locale persisted in
localStorage.

Pages: dashboard (totals, low stock, recent movements), parts list with
search and sort, part create/edit, record movement (in/out/adjust with
smart unit-price and adjust-quantity prefill), suppliers list with
inline add.

Schema: categories, suppliers, parts (with _en/_tg name+description
columns, dirams for money), stock_movements with check on movement_type.
On-hand updates are done in JS inside a transaction with the movement
insert.

Dockerized dev: docker compose, named project, bind-mounted data/ for
DB persistence. Seed contains 6 categories, 4 suppliers, 31 realistic
parts (Lada / Nexia / Opel / Toyota bias).

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

src/routes/parts/new/+page.server.js

@@ -0,0 +1,46 @@
+import { fail, redirect } from '@sveltejs/kit';
+import { createPart, getPartBySku, listCategories } from '$lib/server/parts.js';
+import { recordMovement } from '$lib/server/movements.js';
+
+export function load() {
+  return { categories: listCategories() };
+}
+
+export const actions = {
+  default: async ({ request }) => {
+    const form = await request.formData();
+    const data = Object.fromEntries(form);
+    const errors = validate(data);
+    if (errors) return fail(400, { errors, values: data });
+
+    if (getPartBySku(data.sku.trim())) {
+      return fail(400, { errors: { sku: 'parts.errors.sku_taken' }, values: data });
+    }
+
+    // Save the part with quantity 0, then record an opening "in" movement
+    // if the user supplied an initial quantity. This keeps quantity changes
+    // funneled exclusively through stock_movements.
+    const initialQty = Number(data.quantity_on_hand || 0);
+    const id = createPart({ ...data, quantity_on_hand: 0 });
+    if (initialQty > 0) {
+      recordMovement({
+        part_id: id,
+        movement_type: 'in',
+        quantity: initialQty,
+        unit_price: data.cost_price,
+        reference: 'OPENING'
+      });
+    }
+
+    throw redirect(303, `/parts/${id}`);
+  }
+};
+
+function validate(d) {
+  const errors = {};
+  if (!d.sku || !d.sku.trim()) errors.sku = 'parts.errors.sku_required';
+  if ((!d.name_en || !d.name_en.trim()) && (!d.name_tg || !d.name_tg.trim())) {
+    errors.name = 'parts.errors.name_required';
+  }
+  return Object.keys(errors).length ? errors : null;
+}