test that repros slow list conversation while syncing

[cameronvoell]

Introduction 📟

Purpose ℹ️

Scope 🔭

[macroscopeapp]

Add performance test that reproduces slow list conversation behavior during sync operations in DmTests

• Adds testIfAddressIsOnNetwork2 function to DmTests.swift that measures performance of conversation operations while background sync is running
• Updates libxmtp-swift dependency in Package.swift from version 4.3.2 to commit b33f78e1b6a608be1e42b95f899842a3d0e8823d
• Modifies Client.connectToBackend function call in Client.swift to include appVersion: nil parameter

📍Where to Start

Start with the testIfAddressIsOnNetwork2 function in DmTests.swift to understand the performance testing logic that reproduces the slow list conversation issue.

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Macroscope summarized a5117ae. (Automatic summaries will resume when PR exits draft mode or review begins).