Eliminate Python dependency: embed frontend assets in odoo-go

- Copy all OWL frontend assets (JS/CSS/XML/fonts/images) into frontend/
  directory (2925 files, 43MB) — no more runtime reads from Python Odoo
- Replace OdooAddonsPath config with FrontendDir pointing to local frontend/
- Rewire bundle.go, static.go, templates.go, webclient.go to read from
  frontend/ instead of external Python Odoo addons directory
- Auto-detect frontend/ and build/ dirs relative to binary in main.go
- Delete obsolete Python helper scripts (tools/*.py)

The Go server is now fully self-contained: single binary + frontend/ folder.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

frontend/sale/static/tests/sale_test_helpers.js

@@ -0,0 +1,17 @@
+import { mailModels } from "@mail/../tests/mail_test_helpers";
+import { defineModels } from "@web/../tests/web_test_helpers";
+import { productModels } from "@product/../tests/product_test_helpers";
+import { SaleOrder } from "./mock_server/mock_models/sale_order";
+import { SaleOrderLine } from "./mock_server/mock_models/sale_order_line";
+
+
+export const saleModels = {
+    ...mailModels,
+    ...productModels,
+    SaleOrder,
+    SaleOrderLine,
+};
+
+export function defineSaleModels() {
+    defineModels(saleModels);
+}