feat(docs): Add "High-Performance Indexing" Guide (Graph vs. Goldsky)

[jadonamite]

Description

This PR adds a guide on indexing strategies for Base, focusing on The Graph and Goldsky.

Changes

• New File: apps/base-docs/docs/cookbook/data/high-performance-indexing.md
• Comparison: Detailed analysis of Linear Indexing (The Graph) vs. Parallel Indexing (Goldsky) to help developers choose the right tool for latency-sensitive apps.
• Tutorial: Step-by-step code for initializing, mapping, and deploying a custom subgraph to the Base network.
• Schema Design: Example of an Account/Transfer entity relationship model for tracking ERC-20 balances.

Why

Standard RPC methods (eth_getLogs) are insufficient for production applications. This guide provides the path for developers to migrate to proper indexing solutions, which improves dApp performance and reliability on Base.

[cb-heimdall]

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