feat(admin-*,dashboard): add dashboard i18n extensions (#13763)

* virtual i18n module

* changeset

* fallback ns

fallback to the default "translation" ns if the key isnt found. Allows to use a single "useTranslation("customNs")" hook for both custom and medusa-provided keys

* simplify merges

* optional for backward compat

* fix HMR

* fix generated deepMerge

* test

packages/admin/admin-vite-plugin/src/virtual-modules/generate-virtual-i18n-module.ts

@@ -0,0 +1,27 @@
+import outdent from "outdent"
+import { generateModule } from "../utils"
+import { generateI18n } from "../i18n"
+
+export async function generateVirtualI18nModule(
+    sources: Set<string>,
+    pluginMode = false
+) {
+    const i18n = await generateI18n(sources)
+
+    const imports = [
+        'import { deepMerge } from "@medusajs/admin-shared"',
+        ...i18n.imports
+    ]
+
+    const code = outdent`
+        ${imports.join("\n")}
+
+        ${pluginMode
+            ? `const i18nModule = { ${i18n.code} }`
+            : `export default { ${i18n.code} }`
+        }
+    `
+
+    return generateModule(code)
+}
+

packages/admin/admin-vite-plugin/src/virtual-modules/index.ts

@@ -4,3 +4,4 @@ export * from "./generate-virtual-link-module"
 export * from "./generate-virtual-menu-item-module"
 export * from "./generate-virtual-route-module"
 export * from "./generate-virtual-widget-module"
+export * from "./generate-virtual-i18n-module"