feat(nostr): ancestor 't' tags on menu listings

When a menu item's NIP-99 kind-30402 listing is published, the
extension now emits one 't' tag per ancestor node name (root-first,
slugified to lowercase ASCII). This lets Nostr clients filter the
global listing stream by category — e.g.
    {"#t": ["hot-beverages"]}
    {"#t": ["coffee-based"]}
without having to know the publisher's pubkey or pull markdown
content. The 'menu' anchor stays first so subscribers can still
get the universal stream. Allergen / ingredient prefixes
(allergen:<x>, ingr:<x>) and dietary tags are unchanged.

nostr_publisher.py:
  - Add _slugify(name) -> str (lowercase, [^a-z0-9]+ -> '-', strip).
  - build_menu_item_event takes ancestor_names: tuple[str, ...] kw
    and emits dedup'd slugs. Stays DB-free; the caller does the
    walk.

views_api.py:
  - _ancestor_names_for_node walks the materialized path of an
    item's node to (root.name, ..., leaf.name).
  - _publish_menu_item passes them to the builder.
  - api_update_menu_node detects a name change and calls
    _republish_subtree_items(node_id), which re-publishes every
    menu_item in the subtree so the new ancestor slug lands on
    each listing. <=50 items per restaurant in practice; eager
    re-publish keeps the relay state consistent without a
    background sync.

views_api.py

@@ -157,6 +157,29 @@ async def _publish_restaurant(restaurant: Restaurant) -> None:
         await update_restaurant(restaurant)
 
 
+async def _ancestor_names_for_node(node_id: Optional[str]) -> tuple[str, ...]:
+    """
+    Walk the materialized `path` of a node, returning the chain of
+    node names root-first (including the leaf node itself).
+    Returns () if node_id is None or path can't be resolved.
+    """
+    if not node_id:
+        return ()
+    leaf = await get_menu_node(node_id)
+    if not leaf:
+        return ()
+    ancestor_ids = leaf.path.split("/")
+    if not ancestor_ids:
+        return ()
+    # One round-trip per node — at most MAX_MENU_DEPTH+1 calls (≤4).
+    names: list[str] = []
+    for nid in ancestor_ids:
+        n = await get_menu_node(nid)
+        if n:
+            names.append(n.name)
+    return tuple(names)
+
+
 async def _publish_menu_item(item: MenuItem) -> None:
     settings = await get_settings()
     if not settings.nostr_publish_enabled:
@@ -171,7 +194,10 @@ async def _publish_menu_item(item: MenuItem) -> None:
 
     from . import nostr_client
 
-    event = build_menu_item_event(item, restaurant, pubkey)
+    ancestors = await _ancestor_names_for_node(item.node_id)
+    event = build_menu_item_event(
+        item, restaurant, pubkey, ancestor_names=ancestors
+    )
     published = await publish_event(nostr_client, event, prvkey)
     if published:
         item.nostr_event_id = published.id
@@ -342,7 +368,12 @@ async def api_update_menu_node(
     wallet: WalletTypeInfo = Depends(require_admin_key),
 ) -> MenuNodeRow:
     """Update editable fields (name, description, sort_order, image_url).
-    Tree position changes go through PUT /menu_nodes/{id}/move."""
+    Tree position changes go through PUT /menu_nodes/{id}/move.
+
+    A name change triggers re-publishing every item in the subtree
+    so their NIP-99 listings carry the new ancestor `t` tag. ≤50
+    items per restaurant in practice — eager re-publish is cheap.
+    """
     node = await get_menu_node(node_id)
     if not node:
         raise HTTPException(
@@ -351,11 +382,41 @@ async def api_update_menu_node(
     restaurant = await get_restaurant(node.restaurant_id)
     if restaurant:
         _require_owner(restaurant, wallet)
+    name_changed = node.name != data.name
     node.name = data.name
     node.description = data.description
     node.sort_order = data.sort_order
     node.image_url = data.image_url
-    return await update_menu_node(node)
+    updated = await update_menu_node(node)
+
+    if name_changed:
+        await _republish_subtree_items(node_id)
+
+    return updated
+
+
+async def _republish_subtree_items(node_id: str) -> None:
+    """Re-publish every menu item under the given node's subtree,
+    so its kind-30402 events carry the updated ancestor `t` tag set."""
+    from .crud import db
+
+    rows = await db.fetchall(
+        """
+        SELECT mi.* FROM restaurant.menu_items mi
+        JOIN   restaurant.menu_nodes mn ON mn.id = mi.node_id
+        WHERE  mn.path = (SELECT path FROM restaurant.menu_nodes WHERE id = :nid)
+            OR mn.path LIKE (SELECT path FROM restaurant.menu_nodes WHERE id = :nid) || '/%'
+        """,
+        {"nid": node_id},
+        model=MenuItem,
+    )
+    for it in rows:
+        try:
+            await _publish_menu_item(it)
+        except Exception as ex:
+            logger.warning(
+                f"[RESTAURANT] re-publish failed for item {it.id[:12]}..: {ex}"
+            )
 
 
 @restaurant_api_router.put("/api/v1/menu_nodes/{node_id}/move")