feat: add title to auction results

[jilanglois]

Add title to result options for better readability

[sentry]

Bug: The new BannersAuctionResult schema uses the same title: "Banner Auction" as the existing BannersAuction schema, which can cause class name collisions during client code generation.
_{Severity: MEDIUM}

Suggested Fix

To prevent naming collisions during code generation, differentiate the titles. For example, change the title for BannersAuctionResult to "Banner Auction Result", similar to how Sponsored Listing and Sponsored Listings are used for request/result pairs elsewhere in the file.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent.
Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not
valid.

Location: topsort-api-v2.yml#L1197

Potential issue: The OpenAPI specification adds a new schema `BannersAuctionResult` with
`title: "Banner Auction"` on line 1197. This title is identical to the one used by the
pre-existing `BannersAuction` request schema. According to the project's README, clients
use this specification to generate client libraries. Duplicate schema titles can cause
class name collisions in tools like OpenAPI Generator, leading to build failures when
clients attempt to regenerate their SDKs. This prevents them from adopting the new API
changes.

_{Did we get this right? 👍 / 👎 to inform future reviews.}

[eosorted]

@jilanglois, is this a false positive?