fix(feed): skip zero-amount AuctionSettled events

No-bid auction settlements (common on low-activity DAO days) emit
AuctionSettledEvent with amount "0" + zero-address owner. formatETH
renders "0.00000" as "0.00e+0 ETH" and the winner resolves to
"Unknown", producing misleading "Unknown won #N for 0.00e+0 ETH" feed
cards that appear to be spam from another DAO.

Old feed-events.ts never emitted settled events at all (every auction
rendered as AuctionCreated). Filtering zero-amount settlements keeps
real settlements with actual bids visible while removing the noisy
no-bid cards.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: r4topunk

src/services/feed-events.ts

@@ -403,6 +403,14 @@ function transformEvent(event: SubgraphFeedEvent): FeedEvent[] {
 
     case "AuctionSettledEvent": {
       const e = event as SubgraphAuctionSettled;
+      // Skip no-bid settlements (common on low-activity DAO days).
+      // The subgraph emits `amount: "0"` + zero-address owner when an
+      // auction ends with no bidder; surfacing those as "Auction Won"
+      // cards renders "Unknown won for 0.00e+0 ETH" — noisy and
+      // misleading. Old feed never emitted settled events at all, so
+      // filtering preserves the less-spammy baseline while still
+      // showing real settled auctions with actual winners.
+      if (!e.amount || e.amount === "0") return [];
       return [
         {
           id: `auction-settled-${e.auction.id}`,