BM-2477: Add market efficiency indexer and API endpoints

[willpote]

Adds a market efficiency analysis pipeline that tracks whether provers lock the most profitable available orders. More context and analysis of the metric can be found here.

Includes a new market-efficiency-indexer binary that processes locked requests, computes per-order profitability rankings (with gas-adjusted variants), and aggregates hourly/daily efficiency rates. Also adds API endpoints (/efficiency, /efficiency/aggregates, /efficiency/requests) to serve the results.

Changes

• New efficiency module in the indexer crate with DB layer (db/efficiency.rs) and service logic (efficiency/service.rs)
• market-efficiency-indexer binary with CLI args for lookback window, one-shot mode, and start/end time ranges
• SQL migrations for market_efficiency_orders, hourly/daily aggregates, and gas-adjusted variants
• Four new API routes on the indexer API for summary, aggregates, and per-request efficiency data
• Lambda trigger (market-efficiency-trigger-lambda) and Pulumi infra for deploying as an ECS task
• Dockerfile for the new indexer binary
• Integration tests for the efficiency API endpoints
• Docs for run-market-efficiency-indexer in the indexer-api README

[linear]

BM-2477 Add market efficiency indexer and API endpoints

[jonastheis]

I have reviewed the main logic and extended it a little bit to add the percentile rank. Don't know about the infra/deployment part though.