token owners endpoint in insight playground (#7184)

## [Dashboard] Feature: Update Token and NFT API Endpoints

## Notes for the reviewer

This PR adds a new token endpoint and updates the name of an existing NFT endpoint:

1. Added a new endpoint for getting token owners by contract: `/v1/tokens/owners`
2. Renamed the "Get NFTs by owner" endpoint to simply "Get NFTs" to better reflect its functionality

## How to test

Verify the updated endpoint names appear correctly in the Insight section of the playground.

<!-- This is an auto-generated comment: release notes by coderabbit.ai -->

## Summary by CodeRabbit

- **New Features**
  - Added a new API endpoint for retrieving token owners by contract.

- **Refactor**
  - Renamed the "Get NFTs by owner" endpoint to "Get NFTs" for improved clarity.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

Author: iuwqyir

apps/playground-web/src/app/insight/insightBlueprints.ts

@@ -59,6 +59,11 @@ export const insightBlueprints: MinimalBlueprintSpec[] = [
     id: "tokens",
     name: "Tokens",
     paths: [
+      {
+        name: "Get token owners by contract",
+        path: "/v1/tokens/owners",
+        deprecated: false,
+      },
       {
         name: "Get token transfers by transaction",
         path: "/v1/tokens/transfers/transaction/{transaction_hash}",
@@ -126,7 +131,7 @@ export const insightBlueprints: MinimalBlueprintSpec[] = [
         deprecated: false,
       },
       {
-        name: "Get NFTs by owner",
+        name: "Get NFTs",
         path: "/v1/nfts",
         deprecated: false,
       },