Include `size_on_disk` on `getblockchaininfo`

Description

This issue does not include a description.

Contributor guide

Tech stack

javascriptnodejs

Domain

backendapi

Issue type

feature

DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.

3

Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.

half day

Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.

stale

ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.

needs investigation

Prerequisites

JavaScriptNode.jsbasic blockchain concepts

Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.

30

Research direction

Investigate the `getblockchaininfo` RPC implementation in the hsd codebase, likely in `lib/hs client` or `lib/node`. Look for how other fields like `size on disk` are computed (e.g., via `fs.stat` on blockchain data directory). Check comments in the issue for any pointers. The implementation should add a new field to the response object, possibly by accessing the database size through the storage layer.