feat: extract shop from mp/shop — initial libreshop/shop

Source moved verbatim from mp/shop/ on 2026-04-29; mp was the first
concrete adapter consuming the libreshop toolkit. Builds and publishes
git.librete.ch/libreshop/shop on every main / v* push via the standard
.gitea/workflows/build.yml shared across libreshop components.

tsconfig.json

@@ -0,0 +1,18 @@
+{
+  // https://nuxt.com/docs/guide/concepts/typescript
+  "files": [],
+  "references": [
+    {
+      "path": "./.nuxt/tsconfig.app.json"
+    },
+    {
+      "path": "./.nuxt/tsconfig.server.json"
+    },
+    {
+      "path": "./.nuxt/tsconfig.shared.json"
+    },
+    {
+      "path": "./.nuxt/tsconfig.node.json"
+    }
+  ]
+}