Indexer: public trades and klines endpoints for inference books

[Futurizt]

Transferred from gosh-sh/dexdo-cli#96.

The inference indexer exposes markets/depth but lacks public recent trades, klines and ticker data per inferenceOrderBookAddress. Clients therefore cannot build a real chart, trade tape or 24h statistics without lossy local sampling.

Requested backend surface:

• recent executions with price, ticks, quote amount and timestamp;
• OHLCV buckets, initially 1m/1h/1d;
• optional ticker with last price and 24h change/volume.

This is backend/indexer scope. The CLI may surface these endpoints only after the backend contract exists.