Route Silent Payment indexer connections through Tor

[theanmolsharma]

Problem

The SilentPaymentIndexer currently connects to the indexer over clearnet via IndexerHttpClient, which uses a basic fetch wrapper (util/fetch.ts) with no proxy support. The indexer is available as a Tor hidden service, but there is no mechanism to route requests through Tor.

This leaks metadata — the user's IP address is exposed to the indexer server on every call to /transactions/height/:height, /silent-block/latest-height, and /health.

Current Architecture

• SilentPaymentIndexer (blue_modules/SilentPaymentIndexer.ts) creates an IndexerHttpClient with a plain baseUrl
• IndexerHttpClient (helpers/silent-payments/IndexerHttpClient.ts) calls fetch() directly with no proxy/agent configuration
• SilentPaymentIndexerConfig (helpers/silent-payments/types.ts) has no fields for Tor/proxy settings
• The codebase already has passive .onion awareness in BlueElectrum.ts (extended timeouts for onion peers) and class/lnurl.ts (onion URL detection), but no active SOCKS proxy integration

Requirements

• Route IndexerHttpClient HTTP requests through a SOCKS5 proxy to reach the indexer's .onion address
• Extend SilentPaymentIndexerConfig to accept Tor/proxy configuration (e.g., SOCKS5 host/port, .onion base URL)
• Handle longer latency inherent to Tor (adjust default timeouts for onion connections)
• Fail gracefully if the Tor proxy is unavailable (with a clear error, optionally falling back to clearnet based on user preference)
• Ensure compatibility with React Native's networking layer (react-native-tcp-socket is already a dependency)

Relevant Files

• blue_modules/SilentPaymentIndexer.ts — indexer wrapper
• helpers/silent-payments/IndexerHttpClient.ts — HTTP client (needs proxy support)
• helpers/silent-payments/types.ts — config type definitions
• util/fetch.ts — fetch wrapper (may need SOCKS agent support)

[notTanveer]

taking this